Eighteen minutes ago, 80% of the children in a school field were boys. 58 more children entered the school field. As a result, the number of boys increased by 40% and the number of girls increased by 90%. How many children are in the school field now?
| |
Boys |
Girls |
Total |
| Before |
5 u |
1 u |
6 u |
| Change |
+ 2 u |
+ 0.9 u |
+ 2.9 u |
| After |
7 u |
1.9 u |
8.9 u |
80% =
80100 =
45Number 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 1 u
=
90100 x 1 u
= 0.9 u
Total number of more children who entered the school field
= 2 u + 0.9 u
= 2.9 u
2.9 u = 58
1 u = 58 ÷ 2.9 = 20
Number of children in the school field now
= 7 u + 1.9 u
= 8.9 u
= 8.9 x 20
= 178
Answer(s): 178
