In a hall,
49 of the students wore sweaters. After 410 students who wore sweaters entered the hall, the percentage of students who wore sweaters increased to 90%. How many students in the hall did not wear sweaters?
| |
Wore sweaters |
Did not wear sweaters |
| Before |
4x1 =
4 u |
5x1 =
5 u |
| Change |
+ 410 |
|
| After |
9x5 =
45 u |
1x5 =
5 u |
90% =
90100 =
910The number of students who did not wear sweaters remains unchanged. LCM of 5 and 1 is 5.
Number of students who wore sweaters and left
= 45 u - 4 u
= 41 u
41 u = 410
1 u = 410 ÷ 41 = 10
Number of students who did not wear sweaters
= 5 u
= 5 x 10
= 50
Answer(s): 50
