(a) A man shared his property among his children as follows: Child's name Ann Afia Kojo Nuno Akom Percentage share 5 15 10 45 25 Represent the information o...
Assessment:WAEC SSCE - General Mathematics - 2021Subject:General Mathematics
(a) A man shared his property among his children as follows:
Child's name
Ann
Afia
Kojo
Nuno
Akom
Percentage share
5
15
10
45
25
Represent the information on a pie chart
(b) A box contains 5 red, 3 green and 4 blue identical beads. Calculate the probability th a girl takes away two red beads, one after the other, from the box.
(a) Pie chart of the property share
The shares sum to \(5+15+10+45+25 = 100\). A full circle is \(360^\circ\), so each child's sector angle is their percentage of \(360^\circ\), i.e. percentage \(\times \frac{360}{100} = \text{percentage} \times 3.6^\circ\):
Child
Percentage share (%)
Sector angle
Ann
5
\(\frac{5}{100}\times 360^\circ = 18^\circ\)
Afia
15
\(\frac{15}{100}\times 360^\circ = 54^\circ\)
Kojo
10
\(\frac{10}{100}\times 360^\circ = 36^\circ\)
Nuno
45
\(\frac{45}{100}\times 360^\circ = 162^\circ\)
Akom
25
\(\frac{25}{100}\times 360^\circ = 90^\circ\)
Total
100
\(360^\circ\)
Check: \(18^\circ+54^\circ+36^\circ+162^\circ+90^\circ = 360^\circ\). Drawing a circle and marking each sector with a protractor gives:
Pie chart of the property share: Ann 18°, Afia 54°, Kojo 36°, Nuno 162°, Akom 90° (total 360°).
(b) Probability of taking two red beads, one after the other
The box holds \(5 + 3 + 4 = 12\) identical beads, of which 5 are red. The two beads are taken one after the other without replacement.
For the first draw, 5 of the 12 beads are red:
\[P(\text{1st red}) = \frac{5}{12}.\]
After one red bead is removed, 4 red beads remain out of 11 beads in total:
The shares sum to \(5+15+10+45+25 = 100\). A full circle is \(360^\circ\), so each child's sector angle is their percentage of \(360^\circ\), i.e. percentage \(\times \frac{360}{100} = \text{percentage} \times 3.6^\circ\):
Child
Percentage share (%)
Sector angle
Ann
5
\(\frac{5}{100}\times 360^\circ = 18^\circ\)
Afia
15
\(\frac{15}{100}\times 360^\circ = 54^\circ\)
Kojo
10
\(\frac{10}{100}\times 360^\circ = 36^\circ\)
Nuno
45
\(\frac{45}{100}\times 360^\circ = 162^\circ\)
Akom
25
\(\frac{25}{100}\times 360^\circ = 90^\circ\)
Total
100
\(360^\circ\)
Check: \(18^\circ+54^\circ+36^\circ+162^\circ+90^\circ = 360^\circ\). Drawing a circle and marking each sector with a protractor gives:
Pie chart of the property share: Ann 18°, Afia 54°, Kojo 36°, Nuno 162°, Akom 90° (total 360°).
(b) Probability of taking two red beads, one after the other
The box holds \(5 + 3 + 4 = 12\) identical beads, of which 5 are red. The two beads are taken one after the other without replacement.
For the first draw, 5 of the 12 beads are red:
\[P(\text{1st red}) = \frac{5}{12}.\]
After one red bead is removed, 4 red beads remain out of 11 beads in total: