The ratio of the girls to the boys in a school was 5 : 3. After 23 girls went home and 26 new boys came, there were 11 more girls than boys in the end. Find the number of children in the school in the end.
| |
Girls
(1) |
Boys
(2) |
(3) |
| Before |
5 u |
3 u |
3 u |
| Change |
- 23 |
+ 26 |
+ 26 + 11 = + 37 |
| After |
5 u |
3 u + 26 |
3 u + 37 |
Comparing girls and
boys in the end |
11 more |
|
|
Since the number of girls is 11 more than the number of boys in the end, when we
add 11 to (2) to form (3), the number of girls and boys in the end will be the same.
(1) = (3)
5 u - 23 = 3 u + 37
5 u - 3 u = 37 + 23
2 u = 60
1 u = 60 ÷ 2 = 30
Number of children in the end
= 5 u + 3 u - 23 + 26
= 8 u + 3
= 8 x 30 + 3
= 240 + 3
= 243
Answer(s): 243
