What is the mean deviation of x, 2x, x+1 and 3x. If their mean is 2?
Answer Details
The first step to finding the mean deviation is to calculate the mean of the given numbers. We are told that the mean of x, 2x, x+1, and 3x is 2.
So, we can write an equation:
(x + 2x + x+1 + 3x)/4 = 2
Simplifying this equation, we get:
7x/4 = 2
Multiplying both sides by 4/7, we get:
x = 8/7
Now we can substitute this value of x back into the original numbers:
x = 8/7
2x = 16/7
x+1 = 15/7
3x = 24/7
Next, we need to find the absolute deviation of each number from the mean:
|x - 2| = |8/7 - 2| = 6/7
|2x - 2| = |16/7 - 2| = 2/7
|x+1 - 2| = |15/7 - 2| = 1/7
|3x - 2| = |24/7 - 2| = 10/7
The mean deviation is the average of these absolute deviations:
(6/7 + 2/7 + 1/7 + 10/7)/4 = 19/28
Therefore, the mean deviation of the given numbers is 19/28.
The answer closest to 19/28 among the options provided is 0.5. Therefore, the answer is (A) 0.5.