In a canteen,
47 of the pupils wore vests. After 48 pupils who wore vests entered the canteen, the percentage of pupils who wore vests increased to 80%. How many pupils in the canteen did not wear vests?
|
Wore vests |
Did not wear vests |
Before |
4x1 = 4 u |
3x1 = 3 u |
Change |
+ 48 |
|
After |
4x3 = 12 u |
1x3 = 3 u |
80% =
80100 =
45The number of pupils who did not wear vests remains unchanged. LCM of 3 and 1 is 3.
Number of pupils who wore vests and left
= 12 u - 4 u
= 8 u
8 u = 48
1 u = 48 ÷ 8 = 6
Number of pupils who did not wear vests
= 3 u
= 3 x 6
= 18
Answer(s): 18