PSLE The ratio of the number of windbreakers to that of sweaters in a boutique was 2 : 1 in the end. After 42 sweaters were sold, the ratio of the number of windbreakers to that of sweaters became 9 : 1. What was the total number of windbreakers and sweaters in the boutique in the end?
|
Windbreakers |
Sweaters |
Total |
Before |
2x9 = 18 u |
1x9 = 9 u |
27 u |
Change |
|
- 42 |
|
After |
9x2 = 18 u |
1x2 = 2 u |
20 u |
The number of windbreakers remains unchanged.
Make the number of windbreakers the same.
LCM of 1 and 2 is 18.
Number of sweaters sold
= 9 u - 2 u
= 7 u
1 u = 42 ÷ 7 = 6
Total number of windbreakers and sweaters in the end
= 18 u + 2 u
= 20 u
= 20 x 6
= 120
Answer(s): 120