In July, the ratio of boys and girls in a school's Swimming Club was 4 : 7. In August, 134 new members joined the club. As a result, the ratio of boys to girls in the club became 7 : 6. There were 8 boys in the Swimming Club in July. How many of the new members were girls?
| |
Boys |
Girls |
| Before |
4 u |
7 u |
| Change |
+ 134 |
| After |
7 p |
6 p |
Number of boys at first = 4 u
4 u = 8
1 u = 8 ÷ 4 = 2
Total number of members at first
= 4 u + 7 u
= 11 u
= 11 x 2
= 22
Total number of members in the end
= 22 + 134
= 156
Total number of members in the end
= 7 p + 6 p
= 13 p
13 p = 156
1 p = 156 ÷ 13 = 12
Number of girls in the end
= 6 p
= 6 x 12
= 72
Number of girls at first
= 7 u
= 7 x 2
= 14
Number of new members who were girls
= 72 - 14
= 58
Answer(s): 58
