In March, the ratio of girls and boys in a school's Gardening Club was 3 : 5. In April, 119 new members joined the club. As a result, the ratio of girls to boys in the club became 7 : 6. There were 9 girls in the Gardening Club in March. How many of the new members were boys?
|
Girls |
Boys |
Before |
3 u |
5 u |
Change |
+ 119 |
After |
7 p |
6 p |
Number of girls at first = 3 u
3 u = 9
1 u = 9 ÷ 3 = 3
Total number of members at first
= 3 u + 5 u
= 8 u
= 8 x 3
= 24
Total number of members in the end
= 24 + 119
= 143
Total number of members in the end
= 7 p + 6 p
= 13 p
13 p = 143
1 p = 143 ÷ 13 = 11
Number of boys in the end
= 6 p
= 6 x 11
= 66
Number of boys at first
= 5 u
= 5 x 3
= 15
Number of new members who were boys
= 66 - 15
= 51
Answer(s): 51