In a school field,
910 of the students wore cardigans. After 70 students who wore cardigans left the school field, the percentage of students who wore cardigans decreased to 20%. How many students in the school field did not wear cardigans?
| |
Wore cardigans |
Did not wear cardigans |
| Before |
9x4 =
36 u |
1x4 =
4 u |
| Change |
- 70 |
|
| After |
1x1 =
1 u |
4x1 =
4 u |
20% =
20100 =
15The number of students who did not wear cardigans remains unchanged. LCM of 1 and 4 is 4.
Number of students who wore cardigans and left
= 36 u - 1 u
= 35 u
35 u = 70
1 u = 70 ÷ 35 = 2
Number of students who did not wear cardigans
= 4 u
= 4 x 2
= 8
Answer(s): 8
