In a basketball court,
110 of the girls wore ties. After 560 girls who wore ties entered the basketball court, the percentage of girls who wore ties increased to 90%. How many girls in the basketball court did not wear ties?
| |
Wore ties |
Did not wear ties |
| Before |
1x1 =
1 u |
9x1 =
9 u |
| Change |
+ 560 |
|
| After |
9x9 =
81 u |
1x9 =
9 u |
90% =
90100 =
910The number of girls who did not wear ties remains unchanged. LCM of 9 and 1 is 9.
Number of girls who wore ties and left
= 81 u - 1 u
= 80 u
80 u = 560
1 u = 560 ÷ 80 = 7
Number of girls who did not wear ties
= 9 u
= 9 x 7
= 63
Answer(s): 63
