In a canteen,
57 of the students wore caps. After 15 students who wore caps entered the canteen, the percentage of students who wore caps increased to 80%. How many students in the canteen did not wear caps?
|
Wore caps |
Did not wear caps |
Before |
5x1 = 5 u |
2x1 = 2 u |
Change |
+ 15 |
|
After |
4x2 = 8 u |
1x2 = 2 u |
80% =
80100 =
45The number of students who did not wear caps remains unchanged. LCM of 2 and 1 is 2.
Number of students who wore caps and left
= 8 u - 5 u
= 3 u
3 u = 15
1 u = 15 ÷ 3 = 5
Number of students who did not wear caps
= 2 u
= 2 x 5
= 10
Answer(s): 10