The ratio of the boys to the girls in a kindergarten was 7 : 2. After 25 boys went home and 29 new girls came, there were 6 more boys than girls in the end. Find the number of students in the kindergarten in the end.
|
Boys (1) |
Girls (2) |
(3) |
Before |
7 u |
2 u |
2 u |
Change |
- 25 |
+ 29 |
+ 29 + 6 = + 35 |
After |
7 u |
2 u + 29 |
2 u + 35 |
Comparing boys and girls in the end |
6 more |
|
|
Since the number of boys is 6 more than the number of girls in the end, when we
add 6 to (2) to form (3), the number of boys and girls in the end will be the same.
(1) = (3)
7 u - 25 = 2 u + 35
7 u - 2 u = 35 + 25
5 u = 60
1 u = 60 ÷ 5 = 12
Number of students in the end
= 7 u + 2 u - 25 + 29
= 9 u + 4
= 9 x 12 + 4
= 108 + 4
= 112
Answer(s): 112