In a canteen,
38 of the students wore vests. After 18 students who wore vests left the canteen, the percentage of students who wore vests decreased to 30%. How many students in the canteen did not wear vests?
| |
Wore vests |
Did not wear vests |
| Before |
3x7 =
21 u |
5x7 =
35 u |
| Change |
- 18 |
|
| After |
3x5 =
15 u |
7x5 =
35 u |
30% =
30100 =
310The number of students who did not wear vests remains unchanged. LCM of 5 and 7 is 35.
Number of students who wore vests and left
= 21 u - 15 u
= 6 u
6 u = 18
1 u = 18 ÷ 6 = 3
Number of students who did not wear vests
= 35 u
= 35 x 3
= 105
Answer(s): 105
