In a parade square,
38 of the pupils wore caps. After 54 pupils who wore caps left the parade square, the percentage of pupils who wore caps decreased to 30%. How many pupils in the parade square did not wear caps?
|
Wore caps |
Did not wear caps |
Before |
3x7 = 21 u |
5x7 = 35 u |
Change |
- 54 |
|
After |
3x5 = 15 u |
7x5 = 35 u |
30% =
30100 =
310The number of pupils who did not wear caps remains unchanged. LCM of 5 and 7 is 35.
Number of pupils who wore caps and left
= 21 u - 15 u
= 6 u
6 u = 54
1 u = 54 ÷ 6 = 9
Number of pupils who did not wear caps
= 35 u
= 35 x 9
= 315
Answer(s): 315