In a parade square,
38 of the boys wore glasses. After 153 boys who wore glasses entered the parade square, the percentage of boys who wore glasses increased to 80%. How many boys in the parade square did not wear glasses?
| |
Wore glasses |
Did not wear glasses |
| Before |
3x1 =
3 u |
5x1 =
5 u |
| Change |
+ 153 |
|
| After |
4x5 =
20 u |
1x5 =
5 u |
80% =
80100 =
45The number of boys who did not wear glasses remains unchanged. LCM of 5 and 1 is 5.
Number of boys who wore glasses and left
= 20 u - 3 u
= 17 u
17 u = 153
1 u = 153 ÷ 17 = 9
Number of boys who did not wear glasses
= 5 u
= 5 x 9
= 45
Answer(s): 45
