In a school field,
27 of the pupils wore glasses. After 91 pupils who wore glasses entered the school field, the percentage of pupils who wore glasses increased to 75%. How many pupils in the school field did not wear glasses?
|
Wore glasses |
Did not wear glasses |
Before |
2x1 = 2 u |
5x1 = 5 u |
Change |
+ 91 |
|
After |
3x5 = 15 u |
1x5 = 5 u |
75% =
75100 =
34The number of pupils who did not wear glasses remains unchanged. LCM of 5 and 1 is 5.
Number of pupils who wore glasses and left
= 15 u - 2 u
= 13 u
13 u = 91
1 u = 91 ÷ 13 = 7
Number of pupils who did not wear glasses
= 5 u
= 5 x 7
= 35
Answer(s): 35