In October, the ratio of girls and boys in a school's Gardening Club was 5 : 8. In November, 30 new members joined the club. As a result, the ratio of girls to boys in the club became 4 : 3. There were 10 girls in the Gardening Club in October. How many of the new members were boys?
| |
Girls |
Boys |
| Before |
5 u |
8 u |
| Change |
+ 30 |
| After |
4 p |
3 p |
Number of girls at first = 5 u
5 u = 10
1 u = 10 ÷ 5 = 2
Total number of members at first
= 5 u + 8 u
= 13 u
= 13 x 2
= 26
Total number of members in the end
= 26 + 30
= 56
Total number of members in the end
= 4 p + 3 p
= 7 p
7 p = 56
1 p = 56 ÷ 7 = 8
Number of boys in the end
= 3 p
= 3 x 8
= 24
Number of boys at first
= 8 u
= 8 x 2
= 16
Number of new members who were boys
= 24 - 16
= 8
Answer(s): 8
