In a tuckshop,
67 of the pupils wore spectacles. After 530 pupils who wore spectacles left the tuckshop, the percentage of pupils who wore spectacles decreased to 10%. How many pupils in the tuckshop did not wear spectacles?
| |
Wore spectacles |
Did not wear spectacles |
| Before |
6x9 =
54 u |
1x9 =
9 u |
| Change |
- 530 |
|
| After |
1x1 =
1 u |
9x1 =
9 u |
10% =
10100 =
110The number of pupils who did not wear spectacles remains unchanged. LCM of 1 and 9 is 9.
Number of pupils who wore spectacles and left
= 54 u - 1 u
= 53 u
53 u = 530
1 u = 530 ÷ 53 = 10
Number of pupils who did not wear spectacles
= 9 u
= 9 x 10
= 90
Answer(s): 90
