In a basketball court,
35 of the boys wore cardigans. After 60 boys who wore cardigans entered the basketball court, the percentage of boys who wore cardigans increased to 90%. How many boys in the basketball court did not wear cardigans?
|
Wore cardigans |
Did not wear cardigans |
Before |
3x1 = 3 u |
2x1 = 2 u |
Change |
+ 60 |
|
After |
9x2 = 18 u |
1x2 = 2 u |
90% =
90100 =
910The number of boys who did not wear cardigans remains unchanged. LCM of 2 and 1 is 2.
Number of boys who wore cardigans and left
= 18 u - 3 u
= 15 u
15 u = 60
1 u = 60 ÷ 15 = 4
Number of boys who did not wear cardigans
= 2 u
= 2 x 4
= 8
Answer(s): 8