In a school field,
110 of the boys wore spectacles. After 75 boys who wore spectacles entered the school field, the percentage of boys who wore spectacles increased to 60%. How many boys in the school field did not wear spectacles?
|
Wore spectacles |
Did not wear spectacles |
Before |
1x2 = 2 u |
9x2 = 18 u |
Change |
+ 75 |
|
After |
3x9 = 27 u |
2x9 = 18 u |
60% =
60100 =
35The number of boys who did not wear spectacles remains unchanged. LCM of 9 and 2 is 18.
Number of boys who wore spectacles and left
= 27 u - 2 u
= 25 u
25 u = 75
1 u = 75 ÷ 25 = 3
Number of boys who did not wear spectacles
= 18 u
= 18 x 3
= 54
Answer(s): 54