In June, the ratio of girls and boys in a school's Tennis Club was 4 : 7. In July, 56 new members joined the club. As a result, the ratio of girls to boys in the club became 7 : 6. There were 8 girls in the Tennis Club in June. How many of the new members were boys?
| |
Girls |
Boys |
| Before |
4 u |
7 u |
| Change |
+ 56 |
| After |
7 p |
6 p |
Number of girls 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 + 56
= 78
Total number of members in the end
= 7 p + 6 p
= 13 p
13 p = 78
1 p = 78 ÷ 13 = 6
Number of boys in the end
= 6 p
= 6 x 6
= 36
Number of boys at first
= 7 u
= 7 x 2
= 14
Number of new members who were boys
= 36 - 14
= 22
Answer(s): 22
