Fourteen minutes ago, 60% of the pupils in a school field were boys. 76 more pupils entered the school field. As a result, the number of boys increased by 40% and the number of girls increased by 90%. How many pupils are in the school field now?
| |
Boys |
Girls |
Total |
| Before |
5 u |
2 u |
7 u |
| Change |
+ 2 u |
+ 1.8 u |
+ 3.8 u |
| After |
7 u |
3.8 u |
10.8 u |
60% =
60100 =
35Number of more boys who entered the school field
= 40% x 5 u
=
40100 x 5 u
= 2 u
Number of more girls who entered the school field
= 90% x 2 u
=
90100 x 2 u
= 1.8 u
Total number of more pupils who entered the school field
= 2 u + 1.8 u
= 3.8 u
3.8 u = 76
1 u = 76 ÷ 3.8 = 20
Number of pupils in the school field now
= 7 u + 3.8 u
= 10.8 u
= 10.8 x 20
= 216
Answer(s): 216
