The ratio of the girls to the boys in a kindergarten was 8 : 3. After 29 girls went home and 13 new boys came, there were 8 more girls than boys in the end. Find the number of children in the kindergarten at first.
| |
Girls
(1) |
Boys
(2) |
(3) |
| Before |
8 u |
3 u |
3 u |
| Change |
- 29 |
+ 13 |
+ 13 + 8 = + 21 |
| After |
8 u |
3 u + 13 |
3 u + 21 |
Comparing girls and
boys in the end |
8 more |
|
|
Since the number of girls is 8 more than the number of boys in the end, when we
add 8 to (2) to form (3), the number of girls and boys in the end will be the same.
(1) = (3)
8 u - 29 = 3 u + 21
8 u - 3 u = 21 + 29
5 u = 50
1 u = 50 ÷ 5 = 10
Number of children at first
= 8 u + 3 u
= 11 u
= 11 x 10
= 110
Answer(s): 110
