In May, the ratio of boys and girls in a school's Chess Club was 3 : 8. In June, 88 new members joined the club. As a result, the ratio of boys to girls in the club became 7 : 6. There were 15 boys in the Chess Club in May. How many of the new members were girls?
| |
Boys |
Girls |
| Before |
3 u |
8 u |
| Change |
+ 88 |
| After |
7 p |
6 p |
Number of boys at first = 3 u
3 u = 15
1 u = 15 ÷ 3 = 5
Total number of members at first
= 3 u + 8 u
= 11 u
= 11 x 5
= 55
Total number of members in the end
= 55 + 88
= 143
Total number of members in the end
= 7 p + 6 p
= 13 p
13 p = 143
1 p = 143 ÷ 13 = 11
Number of girls in the end
= 6 p
= 6 x 11
= 66
Number of girls at first
= 8 u
= 8 x 5
= 40
Number of new members who were girls
= 66 - 40
= 26
Answer(s): 26
