PSLE The ratio of the number of coats to that of sweaters in a shopping centre was 4 : 3 at first. After 161 sweaters were sold, the ratio of the number of coats to that of sweaters became 9 : 1. What was the total number of coats and sweaters in the shopping centre at first?
|
Coats |
Sweaters |
Total |
Before |
4x9 = 36 u |
3x9 = 27 u |
63 u |
Change |
|
- 161 |
|
After |
9x4 = 36 u |
1x4 = 4 u |
40 u |
The number of coats remains unchanged.
Make the number of coats the same.
LCM of 3 and 4 is 36.
Number of sweaters sold
= 27 u - 4 u
= 23 u
1 u = 161 ÷ 23 = 7
Total number of coats and sweaters at first
= 36 u + 27 u
= 63 u
= 63 x 7
= 441
Answer(s): 441