In a school field,
18 of the children wore ties. After 506 children who wore ties entered the school field, the percentage of children who wore ties increased to 70%. How many children in the school field did not wear ties?
|
Wore ties |
Did not wear ties |
Before |
1x3 = 3 u |
7x3 = 21 u |
Change |
+ 506 |
|
After |
7x7 = 49 u |
3x7 = 21 u |
70% =
70100 =
710The number of children who did not wear ties remains unchanged. LCM of 7 and 3 is 21.
Number of children who wore ties and left
= 49 u - 3 u
= 46 u
46 u = 506
1 u = 506 ÷ 46 = 11
Number of children who did not wear ties
= 21 u
= 21 x 11
= 231
Answer(s): 231