In March, the ratio of girls and boys in a school's Chess Club was 4 : 7. In April, 48 new members joined the club. As a result, the ratio of girls to boys in the club became 4 : 3. There were 8 girls in the Chess Club in March. How many of the new members were boys?
| |
Girls |
Boys |
| Before |
4 u |
7 u |
| Change |
+ 48 |
| After |
4 p |
3 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 + 48
= 70
Total number of members in the end
= 4 p + 3 p
= 7 p
7 p = 70
1 p = 70 ÷ 7 = 10
Number of boys in the end
= 3 p
= 3 x 10
= 30
Number of boys at first
= 7 u
= 7 x 2
= 14
Number of new members who were boys
= 30 - 14
= 16
Answer(s): 16
