There was an equal number of boys and girls at the computer lab. After
57 of the boys and 47 girls left the computer lab, there were 17 more boys than girls at the computer lab. How many students were there at the computer lab at first?
|
Boys |
Girls |
Before |
7 u |
7 u |
Change |
- 5 u |
- 47 |
After |
2 u |
7 u - 47 |
Number of boys in the end
= 7 u - 5 u
= 2 u
If another 17 girls entered the computer lab, the number of boys and girls would be the same.
7 u - 47 + 17 = 2 u
7 u - 30 = 2 u
7 u - 2 u = 30
5 u = 30
1 u = 30 ÷ 5 = 6
Number of students in the computer lab at first
= 14 u
= 14 x 6
= 84
Answer(s): 84