In April, the ratio of girls and boys in a school's Art Club was 2 : 5. In May, 37 new members joined the club. As a result, the ratio of girls to boys in the club became 5 : 4. There were 10 girls in the Art Club in April. How many of the new members were boys?
| |
Girls |
Boys |
| Before |
2 u |
5 u |
| Change |
+ 37 |
| After |
5 p |
4 p |
Number of girls at first = 2 u
2 u = 10
1 u = 10 ÷ 2 = 5
Total number of members at first
= 2 u + 5 u
= 7 u
= 7 x 5
= 35
Total number of members in the end
= 35 + 37
= 72
Total number of members in the end
= 5 p + 4 p
= 9 p
9 p = 72
1 p = 72 ÷ 9 = 8
Number of boys in the end
= 4 p
= 4 x 8
= 32
Number of boys at first
= 5 u
= 5 x 5
= 25
Number of new members who were boys
= 32 - 25
= 7
Answer(s): 7
