In a parade square,
23 of the students wore glasses. After 117 students who wore glasses left the parade square, the percentage of students who wore glasses decreased to 45%. How many students in the parade square did not wear glasses?
| |
Wore glasses |
Did not wear glasses |
| Before |
2x11 =
22 u |
1x11 =
11 u |
| Change |
- 117 |
|
| After |
9x1 =
9 u |
11x1 =
11 u |
45% =
45100 =
920The number of students who did not wear glasses remains unchanged. LCM of 1 and 11 is 11.
Number of students who wore glasses and left
= 22 u - 9 u
= 13 u
13 u = 117
1 u = 117 ÷ 13 = 9
Number of students who did not wear glasses
= 11 u
= 11 x 9
= 99
Answer(s): 99
