Nine minutes ago, 70% of the children in a school field were boys. 81 more children entered the school field. As a result, the number of boys increased by 30% and the number of girls increased by 80%. How many children are in the school field now?
| |
Boys |
Girls |
Total |
| Before |
10 u |
3 u |
13 u |
| Change |
+ 3 u |
+ 2.4 u |
+ 5.4 u |
| After |
13 u |
5.4 u |
18.4 u |
70% =
70100 =
710Number of more boys who entered the school field
= 30% x 10 u
=
30100 x 10 u
= 3 u
Number of more girls who entered the school field
= 80% x 3 u
=
80100 x 3 u
= 2.4 u
Total number of more children who entered the school field
= 3 u + 2.4 u
= 5.4 u
5.4 u = 81
1 u = 81 ÷ 5.4 = 15
Number of children in the school field now
= 13 u + 5.4 u
= 18.4 u
= 18.4 x 15
= 276
Answer(s): 276
