In a parade square,
310 of the children wore vests. After 160 children who wore vests left the parade square, the percentage of children who wore vests decreased to 10%. How many children in the parade square did not wear vests?
| |
Wore vests |
Did not wear vests |
| Before |
3x9 =
27 u |
7x9 =
63 u |
| Change |
- 160 |
|
| After |
1x7 =
7 u |
9x7 =
63 u |
10% =
10100 =
110The number of children who did not wear vests remains unchanged. LCM of 7 and 9 is 63.
Number of children who wore vests and left
= 27 u - 7 u
= 20 u
20 u = 160
1 u = 160 ÷ 20 = 8
Number of children who did not wear vests
= 63 u
= 63 x 8
= 504
Answer(s): 504
