At the theme park, there were
57 as many girls as boys. After 72 girls came and 12 boys left the theme park, there was an equal number of girls and boys who remained at the theme park. How many children were at the theme park in the end?
| |
Girls |
Boys |
| Before |
5 u |
7 u |
| Change |
+ 72 |
- 12 |
| After |
5 u + 72 |
7 u - 12 |
Number of children in the end is the same.
7 u - 12 = 5 u + 72
7 u - 5 u = 72 + 12
2 u = 84
1 u = 84 ÷ 2 = 42
Number of children in the end
= 2 x (5 u + 72)
= 10 u + 144
= 10 x 42 + 144
= 420 + 144
= 564
Answer(s): 564
