In a canteen,
57 of the girls wore spectacles. After 87 girls who wore spectacles left the canteen, the percentage of girls who wore spectacles decreased to 30%. How many girls in the canteen did not wear spectacles?
| |
Wore spectacles |
Did not wear spectacles |
| Before |
5x7 =
35 u |
2x7 =
14 u |
| Change |
- 87 |
|
| After |
3x2 =
6 u |
7x2 =
14 u |
30% =
30100 =
310The number of girls who did not wear spectacles remains unchanged. LCM of 2 and 7 is 14.
Number of girls who wore spectacles and left
= 35 u - 6 u
= 29 u
29 u = 87
1 u = 87 ÷ 29 = 3
Number of girls who did not wear spectacles
= 14 u
= 14 x 3
= 42
Answer(s): 42
