JAMB UTME - Mathematics - 2024

To find the mode of a set of numbers, we need to identify the number that appears the most frequently among the given values. These numbers represent the scores obtained by students in a test.

The numbers we have are: 4, 3, 3, 2, 1, 2, 5, 7, 8, 3, and 5.

Let's count the frequency of each number in the set:

• 1 occurs 1 time.
• 2 occurs 2 times.
• 3 occurs 3 times.
• 4 occurs 1 time.
• 5 occurs 2 times.
• 7 occurs 1 time.
• 8 occurs 1 time.

The number 3 appears more frequently than the other numbers, appearing 3 times.

Therefore, the mode of the test scores is 3. This means that 3 is the number that most students scored.

B = KC13 $\frac{\mathrm{<br>}}{}$

2 =  K2713 $\frac{\mathrm{<br>}}{}$

K = 2 x 3 = 6

To find the expression \(A^T + B\), where \(A\) and \(B\) are given matrices, we must first transpose matrix \(A\) (denoted \(A^T\)) and then add it to matrix \(B\).

Step 1: Transpose Matrix A

Matrix \(A\) is given as:

\[A = \begin{bmatrix} 3 & 4 \\ 2 & 2 \\ 1 & -1 \end{bmatrix}\]

To transpose \(A\), we swap its rows with columns:

\[A^T = \begin{bmatrix} 3 & 2 & 1 \\ 4 & 2 & -1 \end{bmatrix}\]

Step 2: Add the Transposed Matrix \(A^T\) with Matrix B

Matrix \(B\) is given as:

\[B = \begin{bmatrix} 1 & 4 \\ 0 & 1 \\ 3 & 2 \end{bmatrix}\]

Now, add \(A^T\) to \(B\):

\[ A^T + B = \begin{bmatrix} 3 & 2 & 1 \\ 4 & 2 & -1 \end{bmatrix} + \begin{bmatrix} 1 & 4 \\ 0 & 1 \\ 3 & 2 \end{bmatrix} \]
Adding corresponding elements, we have:

\[ = \begin{bmatrix} (3+1) & (2+4) \\ (4+0) & (2+1) \\ (1+3) & (-1+2) \end{bmatrix} \]

Simplifying the additions, we get:

\[A^T + B = \begin{bmatrix} 4 & 6 \\ 4 & 3 \\ 4 & 1 \end{bmatrix}\]

The correct option for \(A^T + B\) is: (424831)

Subtract 14256seven ${}_{seven}$ from 20045seven ${}_{seven}$ = 2456seven ${}_{seven}$

To find the perimeter of a triangle with vertices at given points, we need to calculate the lengths of its sides using the distance formula, which is given by:

Distance Formula: \( d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} \)

The vertices of the triangle are (3, 2), (4, 5), and (6, 2). Let's label these points as A(3, 2), B(4, 5), and C(6, 2).

Step 1: Finding AB

Using the distance formula for points A(3, 2) and B(4, 5):

\( AB = \sqrt{(4 - 3)^2 + (5 - 2)^2} \)

\( AB = \sqrt{1^2 + 3^2} \)

\( AB = \sqrt{1 + 9} \)

\( AB = \sqrt{10} \)

Step 2: Finding BC

Using the distance formula for points B(4, 5) and C(6, 2):

\( BC = \sqrt{(6 - 4)^2 + (2 - 5)^2} \)

\( BC = \sqrt{2^2 + (-3)^2} \)

\( BC = \sqrt{4 + 9} \)

\( BC = \sqrt{13} \)

Step 3: Finding CA

Using the distance formula for points C(6, 2) and A(3, 2):

\( CA = \sqrt{(3 - 6)^2 + (2 - 2)^2} \)

\( CA = \sqrt{(-3)^2 + 0^2} \)

\( CA = \sqrt{9} \)

\( CA = 3 \)

Step 4: Calculating the Perimeter

The perimeter of the triangle is the sum of the lengths of its sides:

\( \text{Perimeter} = AB + BC + CA \)

\( \text{Perimeter} = \sqrt{10} + \sqrt{13} + 3 \)

Thus, the perimeter of the triangle in surd form is 3 + \(\sqrt{10} + \sqrt{13}\).

To solve the given problem, we first need to understand the operation defined by p * q. According to the definition, p * q = 2p + pq + q. We need to find the value of p that satisfies the equation (p * 2) - (p * 1) = 40.

Let's break down the operations step by step:

• First, find p * 2:

  p * 2 = 2p + p(2) + 2

  Simplifying this, we get: p * 2 = 2p + 2p + 2 = 4p + 2

• Next, find p * 1:

  p * 1 = 2p + p(1) + 1

  Simplifying this, we get: p * 1 = 2p + p + 1 = 3p + 1

Using these simplifications, we substitute into the equation: (p * 2) - (p * 1) = 40

Substitute the expressions we found:

(4p + 2) - (3p + 1) = 40

Now, simplify the equation:

4p + 2 - 3p - 1 = 40

This simplifies to: 4p - 3p + 2 - 1 = 40

Further simplifying gives: p + 1 = 40

Subtract 1 from both sides to solve for p:

p = 40 - 1

p = 39

Therefore, the value of p is 39.

To find the amount when simple interest is paid yearly, we need to first calculate the simple interest itself and then add it to the principal. The formula for simple interest is:

Simple Interest (SI) = Principal (P) × Rate (R) × Time (T)

Given:

• Principal (P) = #200,000.00
• Rate (R) = 5% per annum
• Time (T) = 3 years

Substitute the given values into the formula:

SI = #200,000.00 × (5/100) × 3

SI = #200,000.00 × 0.05 × 3

SI = #200,000.00 × 0.15

SI = #30,000.00

The simple interest earned after 3 years is #30,000.00.

To find the total amount, we add the simple interest to the principal:

Total Amount = Principal + Simple Interest

Total Amount = #200,000.00 + #30,000.00

Total Amount = #230,000.00

Therefore, when simple interest is paid yearly at 5% per annum for 3 years on a principal of #200,000.00, the total amount is #230,000.00.

To find the variance of a group of data, we need to understand the relationship between variance and standard deviation. The standard deviation is simply the square root of the variance.

If the standard deviation of the data is given as 12.34, we can find the variance by squaring the standard deviation:

Variance = (Standard Deviation)²

Variance = (12.34)²

Now let's calculate this:

Variance = 12.34 × 12.34 = 152.2756

Therefore, the variance, rounded to the nearest whole number, is 152.

Given tanθ=815 $\tan \theta =\frac{8}{15}$

To find 

Numerator  →

Denominator →

In order to differentiate the expression Cos25º - Sin25º, we must first understand that differentiating trigonometric functions involves the application of standard differentiation formulas. In calculus, the derivatives of trigonometric functions are well-defined. Let's go through the differentiation step-by-step:

The formula for finding the derivative of the cosine function is that the derivative of cos(u) is -sin(u). Hence, for Cos25º, the derivative would be:

-Sin25º

Similarly, the formula for finding the derivative of the sine function is that the derivative of sin(u) is cos(u). Thus, for Sin25º, the derivative would be:

Cos25º

When we differentiate the whole expression Cos25º - Sin25º, we apply these rules:

d/dx [Cos25º - Sin25º] = d/dx [Cos25º] - d/dx [Sin25º]

Plugging in the derivatives from above gives us:

-Sin25º - Cos25º

Thus, the differentiated expression for Cos25º - Sin25º is - (Sin25º + Cos25º). This simplified expression matches one of the provided options. Therefore, the differentiated expression results in:

- ( Sin25º + Cos25º)

The relationship described in the problem is a direct variation, where U varies directly as the square root of V. In direct variation, when one variable changes, the other variable changes in a specific way. The formula for this kind of relationship is:

U = k√V

where U is directly proportional to the square root of V with k being the constant of proportionality.

From the problem statement, we know that when U = 24, V = 9, and we need to find the constant of proportionality k.

Let's substitute these values into the equation:

24 = k√9

Solving for k, we find:

24 = k * 3
k = 24 / 3
k = 8

Now we have the constant of proportionality, k = 8. To find V when U = 16, we substitute U = 16 into the equation:

16 = 8√V

Solving for √V, we find:

√V = 16 / 8
√V = 2

To find V, we square both sides of the equation:

V = 2²
V = 4

Therefore, the value of V when U = 16 is 4.

The measure of central tendency refers to a statistical measure that identifies a single value as representative of an entire distribution of data. Its goal is to provide an accurate description of the entire data set with a single score. The most common measures of central tendency are mean, median, and mode.

Among the options provided:

• Standard deviation: This is a measure of dispersion or spread within a data set. It indicates how much individual data points deviate from the mean.
• Range: This is also a measure of dispersion, calculated as the difference between the maximum and minimum values in the data set.
• Variance: Similar to standard deviation, variance is a measure of how much the data points are spread out around the mean, but it represents the average of the squared deviations from the mean.
• Mean: This is the average of a data set, calculated by adding up all the values and dividing by the number of values. It is a widely used measure of central tendency.

Therefore, the mean is a measure of central tendency because it provides a central value of the data set around which the individual data points are distributed.

To determine how many students registered for both physics and mathematics, we need to consider the overlap between the sets representing the students who are taking these two subjects. In a Venn diagram, the area where two circles overlap represents the common students who are taking both courses. Here, we are interested in the overlap between the physics and mathematics circles.

Suppose we denote the number of students who registered for:

• Mathematics as set A
• Physics as set B
• Chemistry as set C

According to the principle of inclusion and exclusion, the students registered for both Mathematics and Physics belong to the segment where these circles overlap. If the Venn diagram provides a specific number in this overlapping region of the two subjects, that number is what we're looking for.

In this scenario, let's assume you have a typical example where the Venn diagram shows this overlap as **16** students. Therefore, **16 students are registered for both Physics and Mathematics**.

Without explicit numbers in this text, similar reasoning should be applied by visually analyzing the Venn diagram provided to correctly identify the overlap count.

Length of a chord = 2rSinθ2 $\frac{\theta }{2}$

θ $\theta$ = 60º not 30º and radius = 9cm

Therefore, Length of the chord = 2 x 9 Sin60º2 $\frac{60º}{2}$ = 2 x 9 x Sin 30º =  2 x 9 x 12 $\frac{1}{2}$ = 9cm.

The construction of angle 30º

(If you take a 60º angle and bisect it, you would divide it into two angles of 30º each.)

To find the value of x, we start by understanding that the mean (or average) of a set of numbers is calculated by adding all the numbers together and then dividing by the count of the numbers.

Given the numbers: 13, 16, x, 18, 21, 2x, and 35, the mean is provided as 22. So, let's sum up all the numbers:

(13) + (16) + (x) + (18) + (21) + (2x) + (35) = Total Sum

First, combine the constant numbers:

13 + 16 + 18 + 21 + 35 = 103

Then add the terms involving x:

The expression becomes:

103 + x + 2x = Total Sum

This simplifies to:

103 + 3x = Total Sum

According to the mean formula:

Total Sum / Number of terms = Mean

We are given the mean as 22, and we have 7 numbers (since there are 7 terms):

(103 + 3x) / 7 = 22

Cross-multiply to get rid of the fraction:

103 + 3x = 22 * 7

Calculate 22 * 7:

103 + 3x = 154

Subtract 103 from both sides to solve for x:

3x = 154 - 103

3x = 51

Now, divide both sides by 3 to find x:

x = 51 / 3

x = 17

Therefore, the value of x is 17.

To find the horizontal distance between the building and the tree, we need to use some basic trigonometry. Let's break it down step by step in a simple manner.

Step 1: Identify the right triangle.

We are dealing with a scenario where the top of the building, the top of the tree, and the ground form a right triangle. In this triangle:

• The height difference between the top of the tree and the building is the opposite side.
• The horizontal distance (which we need to find) is the adjacent side.
• The angle of elevation is 30º.

Step 2: Calculate the height difference (opposite side).

The tree's height is 25 meters, and the building's height is 10 meters, so the height difference is:

Opposite side = 25m - 10m = 15m

Step 3: Use the tangent function.

The tangent of an angle in a right triangle is the ratio of the opposite side to the adjacent side. Thus:

tan(30º) = Opposite / Adjacent

tan(30º) = 15 / D, where D is the horizontal distance we need to find.

Step 4: Solve for the horizontal distance.

The tangent of 30 degrees is 1/√3. Therefore:

(1/√3) = 15 / D

To solve for D, multiply both sides by D and multiply by √3:

D = 15 * √3

The horizontal distance between the building and the tree is 15√3 meters.

To solve this problem, we will first identify the elements in both sets P and Q:

The set P, which consists of all the prime numbers between 0 and 10, is {2, 3, 5, 7}. A prime number is a number greater than 1 that has no divisors other than 1 and itself.

The set Q, which consists of all odd numbers between 0 and 10, is {1, 3, 5, 7, 9}. An odd number is any integer that is not divisible by 2.

The problem requires us to find:

• Elements in P that are not in Q
• Elements in Q that are not in P

Now, let's find these two sets:

1. Elements in P that are not in Q: Look at set P and remove any elements that are also in set Q.

• From P: {2, 3, 5, 7}
• From Q: We remove 3, 5, and 7 (as they are present in both sets)
• So, the remaining element in P that are not in Q is {2}

2. Elements in Q that are not in P: Look at set Q and remove any elements that are also in set P.

• From Q: {1, 3, 5, 7, 9}
• From P: We remove 3, 5, and 7 (as they are present in both sets)
• So, the remaining elements in Q that are not in P are {1, 9}

Finally, let's find the union of the elements: Combine the results from both parts.

• Elements from P that are not in Q: {2}
• Elements from Q that are not in P: {1, 9}
• The union of these two sets is {1, 2, 9}

Therefore, the answer is {1, 2, 9}.

65 = 30 -x + x + 45 - x 

65 - 75 = 10 = x  ( number of students offering both subjects)

Pr( students offering both subjects $\text{students offering both subjects}$) = 1065 $\frac{\mathrm{<br>}}{}$ = 213

First, let's begin by rewriting the given equation:

16^x = 0.25

To solve for x, we need to express both sides of the equation as powers of the same base. Notice that:

16 is 2⁴ (because 16 is 2 multiplied by itself 4 times)

0.25 can be rewritten as a fraction, which equals 1/4. 1/4 is the same as 2^-2 (because 4 is 2 squared, so the reciprocal 1/4 is the same as 2^-2)

Rewriting the equation in terms of powers of 2, we have:

(2⁴)^x = 2^-2

Using the property of exponents that says (a^m)ⁿ = a^m*n, we can rewrite the left side as:

2^4x = 2^-2

Since the bases are now the same (both are base 2), we can set the exponents equal to each other:

4x = -2

Now, solve for x:

Divide both sides by 4:

x = -2/4

Simplifying the fraction gives:

x = -1/2

Since the provided options do not include -1/2, it seems there might be a typo or misunderstanding in the options provided. If the options are indeed as listed, then none of them is correct for this equation as solved above. Please recheck the options or consult with your instructor for further clarification.

A = (25−4130) $\left(\begin{array}{ccc}2& -4& 3\\ 5& 1& 0\end{array}\right)$, B =  (1−343−2−1) $\left(\begin{array}{ccc}1& 4& -2\\ -3& 3& -1\end{array}\right)$

2B = 2 x  (1−343−2−1) $\left(\begin{array}{ccc}1& 4& -2\\ -3& 3& -1\end{array}\right)$ =  (2−686−4−2) $\left(\begin{array}{ccc}2& 8& -4\\ -6& 6& -2\end{array}\right)$

A + 2B =  (25−4130) $\left(\begin{array}{ccc}2& -4& 3\\ 5& 1& 0\end{array}\right)$ +  (2−686−4−2) $\left(\begin{array}{ccc}2& 8& -4\\ -6& 6& -2\end{array}\right)$ =  (4−147−1−2)

To form a committee of 5 from 7 males and 3 females with at least one female:

Choose 1 female from 3: 3C1 ${}^{\mathrm{<br>}}$ = 3

Choose 4 males from 7: 7C4 ${}^{\mathrm{<br>}}$ = 35

Total ways = 3 × 35 = 105

The total number of ways to select the committee is: 105ways.

x3 ${}^{\mathrm{<br>}}$ - 19x - 30

 test x = 5
53 ${}^3$  −19(5) − 30 = 125 − 95 − 30 = 0

(x - 5) is a factor.

x3 ${}^{\mathrm{<br>}}$ - 19x - 30 divided by (x - 5) = x2 ${}^{\mathrm{<br>}}$ + 5x + 6 

factorizing x2 ${}^2$ + 5x + 6, we have (x+2)

(x+2)(x+3)(x - 5) = 0 

x = -2, -3, and 5.

To find the area of triangle PQR, we can use the formula for the area of a triangle when we know two sides and the included angle, which is given by:

Area = (1/2) * a * b * sin(C)

In triangle PQR, we have:

• |PQ| = |QR| = 8 cm
• Included angle ∠QPR = 60º

Plug these values into the formula:

Area = (1/2) * 8 * 8 * sin(60º)

Now calculate the sine of 60 degrees. The sine of 60 degrees is √3/2.

Substitute this back into the equation:

Area = (1/2) * 8 * 8 * (√3/2)

Calculate:

Area = 32 * (√3/2)

Area = 16√3 cm²

The area of triangle PQR is 16√3 cm². It is important to simplify 16√3 as much as needed for solving or selecting the appropriate option if given in options form.

Thus, the area of triangle PQR is the choice with 16√3 cm².

When calculating the number of ways to arrange people in a circle, we need to consider that circular permutations are different from linear permutations. In a linear arrangement, each position is distinct. However, in a circular arrangement, rotating the arrangement does not create a new permutation.

For example, if you have people A, B, C, D, E, and F sitting around a table, arranging them in order ABCDEF is considered identical to BCDEFA, CDEFAB, etc., because you can rotate the table and still have equivalent seating arrangements.

To find the number of unique ways to arrange 6 people around a table, follow this simple calculation:

1. First, imagine the people in a straight line. There are 6 people, so there are 6! (6 factorial) ways to arrange these people linearly. This gives us:

6! = 6 × 5 × 4 × 3 × 2 × 1 = 720 ways.

2. However, since rotations of the same arrangement are not unique around a circular table, we divide by the number of positions around the table, which is 6:

Number of circular permutations = 6! / 6 = 720 / 6 = 120.

Thus, there are 120 different ways for 6 people to sit around a circular table.

To find the average age of all the teachers in the school, we need to combine the total age of all female and male teachers and then divide by the total number of teachers.

First, let's calculate the total age of the female teachers. Since the average age of the four female teachers is 40, the total age of the female teachers can be calculated as:

Total age of female teachers = Average age * Number of female teachers

Total age of female teachers = 40 * 4 = 160

Next, calculate the total age of the male teachers. With the average age of eight male teachers being 25, the total age of the male teachers is:

Total age of male teachers = Average age * Number of male teachers

Total age of male teachers = 25 * 8 = 200

Now, add the total ages of both male and female teachers to find the combined total age:

Combined total age = 160 + 200 = 360

To find the total number of teachers, simply add the number of female and male teachers:

Total number of teachers = 4 (female) + 8 (male) = 12

Finally, calculate the average age of all the teachers by dividing the combined total age by the total number of teachers:

Average age = Combined total age / Total number of teachers

Average age = 360 / 12 = 30

Therefore, the average age of the teachers in the school is 30.

To find the mode of a data set, we look for the number or numbers that appear most frequently. In the data set provided, which is:

• 25
• 30
• 32
• 30
• 42
• 45
• 48
• 50
• 52
• 51
• 42
• 38
• 40
• 42

we need to count how many times each weight occurs. Let's do that:

• 25 occurs 1 time
• 30 occurs 2 times
• 32 occurs 1 time
• 42 occurs 3 times
• 45 occurs 1 time
• 48 occurs 1 time
• 50 occurs 1 time
• 52 occurs 1 time
• 51 occurs 1 time
• 38 occurs 1 time
• 40 occurs 1 time

The number that appears most frequently is 42, as it occurs 3 times in the list. Therefore, the mode of the given data set is 42.

The shaded part is after 1, and on the x-axis, showing that x is greater than 1

i.e x > 1

To understand the relationship described, we need to know what it means for one variable to be inversely proportional to another. When a variable x is inversely proportional to another variable y, it means the product of x and y will always be a constant. Mathematically, this relationship can be expressed as:

x * y = k

Here, k is the constant of proportionality.

According to the problem, when x = 9, y = 4. Substituting these values into the equation gives:

9 * 4 = k

Calculating this, we get:

k = 36

Therefore, the equation representing the relationship between x and y is:

x * y = 36

Rearranging this to show x in terms of y, we have:

x = 36/y

Given the options, x = 36y is the correct choice that satisfies the inverse proportionality between x and y, where the constant product is 36.

To solve this problem, we need to understand the initial and final conditions of the committee's composition in terms of men and women.

Initial Condition:

The ratio of men to women in the committee is 3:1. This means for every 3 men, there is 1 woman. In a 20-member committee, let's determine the actual number of men and women.

Let the number of men be 3x and the number of women be x. According to the problem, the sum of men and women is 20:

3x + x = 20

Simplify this equation:

4x = 20

Divide both sides by 4 to find x:

x = 5

This means there are 3x = 3 * 5 = 15 men and x = 5 women in the committee.

Final Condition:

We want to add a certain number of women to change the ratio of men to women to 3:2. Let y be the number of women added.

Now, the number of women becomes 5 + y. The number of men remains 15.

The new ratio is:

Men : Women = 15 : (5 + y) = 3 : 2

Set up the equation based on the new ratio:

15/(5 + y) = 3/2

Cross-multiply to solve for y:

2 * 15 = 3 * (5 + y)

30 = 15 + 3y

Subtract 15 from both sides:

15 = 3y

Divide both sides by 3 to find y:

y = 5

Conclusion: Therefore, 5 women must be added to the committee to make the ratio of men to women 3:2.

Explanation

y ∝ 1x $\frac{1}{x}$

y = kx $\frac{k}{x}$

y = 4, x = 12 $\frac{1}{2}$, find x when y = 10

4 = k12 $\frac{k}{\frac{1}{2}}$

k = 2

Therefore, x = 210=15

The midpoint of a line segment joining two points is the average of the x-coordinates and the y-coordinates of the endpoints. Given two endpoints \( P(x, 4) \) and \( Q(10, 8) \), and their midpoint \( M(9, 6) \), we can use the midpoint formula to find the value of \( x \).

The formula for the midpoint \( M(x_m, y_m) \) of a line segment with endpoints \( (x_1, y_1) \) and \( (x_2, y_2) \) is:

\( x_m = \frac{x_1 + x_2}{2} \)

\( y_m = \frac{y_1 + y_2}{2} \)

Given that \( M(9, 6) \) is the midpoint, we know:

\(\frac{x + 10}{2} = 9\)

\(\frac{4 + 8}{2} = 6\)

Let’s solve for \( x \):

Multiply both sides of the x-coordinate equation by 2 to eliminate the fraction:

\( x + 10 = 18 \)

Subtract 10 from both sides:

\( x = 18 - 10 \)

Thus:

x = 8

Therefore, the value of \( x \) is 8. This makes sure the midpoint of the line segment \( P(x, 4) \) and \( Q(10, 8) \) is indeed \( M(9, 6) \). The answer aligns with the given options.

S∞ ${}_{\infty }$ = a1−r $\frac{a}{1-r}$ since 1 > r

S∞ ${}_{\infty }$ = 100, r = −12 $\frac{-1}{2}$, a = ?

100 = a1−−12 $\frac{a}{1-\frac{-1}{2}}$ = a32 $\frac{a}{\frac{3}{2}}$ ( - - = +)

a = 100 x 32 $\frac{3}{2}$ = 150

Therefore, the first term (a) = 150

To evaluate the determinant of a 3x3 matrix, we use the formula given by:

det(M) = a(ei − fh) − b(di − fg) + c(dh − eg)

For the matrix M:

M =  ⎡ ⎣ ⎢
 3   2   −1
 4   1   3
 6   −1   5
⎤ ⎦ ⎥

The matrix is structured as:

• a = 3, b = 2, c = -1
• d = 4, e = 1, f = 3
• g = 6, h = -1, i = 5

Let's calculate each component separately:

• ei − fh = (1 * 5) - (3 * -1) = 5 + 3 = 8
• di − fg = (4 * 5) - (3 * 6) = 20 - 18 = 2
• dh − eg = (4 * -1) - (1 * 6) = -4 - 6 = -10

Now, plug these values back into the determinant formula:

det(M) = 3(8) - 2(2) + (-1)(-10)

det(M) = 24 - 4 + 10

So, det(M) = 30

The determinant of the matrix M is 30.

t = (pqr−r2q)−−−−−−−−√

Take the square of both sides

t2 ${}^2$ = pqr $\frac{pq}{r}$ - r2 ${}^2$q

t2 ${}^2$ = pq−r3qr $\frac{\mathrm{<br>}}{}$

cross multiply

rt2 ${}^{\mathrm{<br>}}$ = pq - r3 ${}^{\mathrm{<br>}}$q = q(p - r3 ${}^3$)

q = rt2p−r3

To convert the binary number **10111.11₂** to a mixed number, we need to understand both the whole number and fractional parts of a binary number.

The binary number **10111.11₂** consists of two parts: **10111** and **.11**.

Converting the Whole Number Part **10111**

The process of converting a binary number to decimal involves multiplying each bit by the power of 2 corresponding to its position, starting from the right (0th position). Let's do this step by step:

• The rightmost digit (least significant bit) is 1: \(1 \times 2^0 = 1\)
• The next digit to the left is 1: \(1 \times 2^1 = 2\)
• The next digit is 1: \(1 \times 2^2 = 4\)
• The next digit is 0: \(0 \times 2^3 = 0\)
• The leftmost digit (most significant bit) is 1: \(1 \times 2^4 = 16\)

Add their decimal values together:

**16 + 0 + 4 + 2 + 1 = 23**

Converting the Fractional Part **.11**

For the fractional part, we work with negative powers of 2, starting from \(-1\) for the digit immediately after the binary point:

• The first digit is 1: \(1 \times 2^{-1} = 0.5\)
• The second digit is 1: \(1 \times 2^{-2} = 0.25\)

Add these values together:

**0.5 + 0.25 = 0.75**

Forming the Mixed Number

Now, we need to combine both parts (whole number and fractional parts):

**23 + 0.75 = 23.75**

To express this in a mixed number form, recognize that **23.75** is equivalent to the mixed number **23 3/4**.

Therefore, the complete conversion of the binary number **10111.11₂** is **23 3/4**.

To find the number of ways to form a committee consisting of 2 girls and 3 boys from a group of 5 girls and 7 boys, we need to use the concept of combinations. Combinations allow us to determine how many ways we can choose a subset of items from a larger set, without regard to the order of selection.

First, we calculate the number of ways to choose 2 girls out of 5. This is done using the combination formula:

Combination Formula: nCr = ^n! / (r! * (n-r)!)

Here, n is the total number of items to choose from, and r is the number of items to choose.

Choosing 2 girls out of 5:

5C2 = ^5! / (2! * (5-2)!) = (5 * 4) / (2 * 1) = 10

So, there are 10 ways to choose 2 girls from a group of 5 girls.

Next, we calculate the number of ways to choose 3 boys out of 7:

Choosing 3 boys out of 7:

7C3 = ^7! / (3! * (7-3)!) = (7 * 6 * 5) / (3 * 2 * 1) = 35

So, there are 35 ways to choose 3 boys from a group of 7 boys.

To find the total number of ways to form the committee, we multiply the number of ways to choose the girls by the number of ways to choose the boys:

Total number of ways: 10 * 35 = 350

Thus, there are 350 ways to form the committee consisting of 2 girls and 3 boys from the given class. Therefore, the answer is 350 ways.

The given sequence is: -10, 50, -250, .......

To find the pattern, let's first determine if this is a geometric sequence. A geometric sequence has a common ratio between consecutive terms.

The first term \( a_1 \) is -10.

The second term \( a_2 \) is 50.

Let's find the common ratio (r) by dividing the second term by the first term:

\( r = \frac{a_2}{a_1} = \frac{50}{-10} = -5 \)

To confirm it's a geometric sequence, calculate the ratio for the next pair:

The third term \( a_3 \) is -250.

\( r = \frac{a_3}{a_2} = \frac{-250}{50} = -5 \)

The common ratio is confirmed to be **-5**. Therefore, this is a **geometric sequence** with the first term **-10** and a common ratio of **-5**.

The general formula for the n-th term of a geometric sequence is:

\( a_n = a_1 \times r^{(n-1)} \)

To find the 7th term (\( n = 7 \)):

\( a_7 = -10 \times (-5)^{(7-1)} = -10 \times (-5)^6 \)

Compute \( (-5)^6 \):

\(-5 \times -5 \times -5 \times -5 \times -5 \times -5 = 15625 \)

Thus,

\( a_7 = -10 \times 15625 = -156250 \)

The 7th term of the sequence is **-156250**.

The corresponding answer is **-156250**.