Seventeen minutes ago, 60% of the pupils in a canteen were girls. 12 more pupils entered the canteen. As a result, the number of girls increased by 20% and the number of boys increased by 70%. How many pupils are in the canteen now?
| |
Girls |
Boys |
Total |
| Before |
5 u |
2 u |
7 u |
| Change |
+ 1 u |
+ 1.4 u |
+ 2.4 u |
| After |
6 u |
3.4 u |
9.4 u |
60% =
60100 =
35Number of more girls who entered the canteen
= 20% x 5 u
=
20100 x 5 u
= 1 u
Number of more boys who entered the canteen
= 70% x 2 u
=
70100 x 2 u
= 1.4 u
Total number of more pupils who entered the canteen
= 1 u + 1.4 u
= 2.4 u
2.4 u = 12
1 u = 12 ÷ 2.4 = 5
Number of pupils in the canteen now
= 6 u + 3.4 u
= 9.4 u
= 9.4 x 5
= 47
Answer(s): 47
