Eighteen minutes ago, 70% of the pupils in a canteen were girls. 38 more pupils entered the canteen. As a result, the number of girls increased by 20% and the number of boys increased by 60%. How many pupils are in the canteen now?
| |
Girls |
Boys |
Total |
| Before |
10 u |
3 u |
13 u |
| Change |
+ 2 u |
+ 1.8 u |
+ 3.8 u |
| After |
12 u |
4.8 u |
16.8 u |
70% =
70100 =
710Number of more girls who entered the canteen
= 20% x 10 u
=
20100 x 10 u
= 2 u
Number of more boys who entered the canteen
= 60% x 3 u
=
60100 x 3 u
= 1.8 u
Total number of more pupils who entered the canteen
= 2 u + 1.8 u
= 3.8 u
3.8 u = 38
1 u = 38 ÷ 3.8 = 10
Number of pupils in the canteen now
= 12 u + 4.8 u
= 16.8 u
= 16.8 x 10
= 168
Answer(s): 168
