In a basketball court,
35 of the boys wore vests. After 30 boys who wore vests left the basketball court, the percentage of boys who wore vests decreased to 30%. How many boys in the basketball court did not wear vests?
| |
Wore vests |
Did not wear vests |
| Before |
3x7 =
21 u |
2x7 =
14 u |
| Change |
- 30 |
|
| After |
3x2 =
6 u |
7x2 =
14 u |
30% =
30100 =
310The number of boys who did not wear vests remains unchanged. LCM of 2 and 7 is 14.
Number of boys who wore vests and left
= 21 u - 6 u
= 15 u
15 u = 30
1 u = 30 ÷ 15 = 2
Number of boys who did not wear vests
= 14 u
= 14 x 2
= 28
Answer(s): 28
