In July, the ratio of boys and girls in a school's Bowing Club was 2 : 5. In August, 70 new members joined the club. As a result, the ratio of boys to girls in the club became 4 : 3. There were 4 boys in the Bowing Club in July. How many of the new members were girls?
| |
Boys |
Girls |
| Before |
2 u |
5 u |
| Change |
+ 70 |
| After |
4 p |
3 p |
Number of boys at first = 2 u
2 u = 4
1 u = 4 ÷ 2 = 2
Total number of members at first
= 2 u + 5 u
= 7 u
= 7 x 2
= 14
Total number of members in the end
= 14 + 70
= 84
Total number of members in the end
= 4 p + 3 p
= 7 p
7 p = 84
1 p = 84 ÷ 7 = 12
Number of girls in the end
= 3 p
= 3 x 12
= 36
Number of girls at first
= 5 u
= 5 x 2
= 10
Number of new members who were girls
= 36 - 10
= 26
Answer(s): 26
