In a canteen,
310 of the children wore glasses. After 108 children who wore glasses entered the canteen, the percentage of children who wore glasses increased to 75%. How many children in the canteen did not wear glasses?
| |
Wore glasses |
Did not wear glasses |
| Before |
3x1 =
3 u |
7x1 =
7 u |
| Change |
+ 108 |
|
| After |
3x7 =
21 u |
1x7 =
7 u |
75% =
75100 =
34The number of children who did not wear glasses remains unchanged. LCM of 7 and 1 is 7.
Number of children who wore glasses and left
= 21 u - 3 u
= 18 u
18 u = 108
1 u = 108 ÷ 18 = 6
Number of children who did not wear glasses
= 7 u
= 7 x 6
= 42
Answer(s): 42
