At the concert hall, there were
18 as many boys as girls. After 78 boys came and 20 girls left the concert hall, there was an equal number of boys and girls who remained at the concert hall. How many children were at the concert hall in the end?
|
Boys |
Girls |
Before |
1 u |
8 u |
Change |
+ 78 |
- 20 |
After |
1 u + 78 |
8 u - 20 |
Number of children in the end is the same.
8 u - 20 = 1 u + 78
8 u - 1 u = 78 + 20
7 u = 98
1 u = 98 ÷ 7 = 14
Number of children in the end
= 2 x (1 u + 78)
= 2 u + 156
= 2 x 14 + 156
= 28 + 156
= 184
Answer(s): 184