Last year, there were 180 members in a school circus show club. The number of girls was
13 the number of boys.
- What percentage of the members were girls last year?
- This year, 9 boys left the club and 9 girls joined the club. What percentage of the members are girls this year?
(a)
Girls : Boys : Total
1 : 3 : 4
Percentage of members that were girls
=
14 x 100%
= 25%
(b)
|
Girls |
Boys |
Before |
1 u |
3 u |
Change |
+ 9 |
- 9 |
After |
1 u + 9 |
3 u - 9 |
4 u = 180
1 u = 180 ÷ 4 = 45
Number of girls this year
= 1 u + 9
= (1 x 45) + 9
= 45 + 9
= 54
Total members this year
= 180 + 9 - 9
= 180
Percentage of girls in the club
=
54180 x 100%
= 30%
Answer(s): (a) 25%; (b) 30%