PSLE The ratio of the number of jackets to that of sweaters in a shop was 2 : 1 at first. After 15 sweaters were sold, the ratio of the number of jackets to that of sweaters became 7 : 1. What was the total number of jackets and sweaters in the shop at first?
|
Jackets |
Sweaters |
Total |
Before |
2x7 = 14 u |
1x7 = 7 u |
21 u |
Change |
|
- 15 |
|
After |
7x2 = 14 u |
1x2 = 2 u |
16 u |
The number of jackets remains unchanged.
Make the number of jackets the same.
LCM of 1 and 2 is 14.
Number of sweaters sold
= 7 u - 2 u
= 5 u
1 u = 15 ÷ 5 = 3
Total number of jackets and sweaters at first
= 14 u + 7 u
= 21 u
= 21 x 3
= 63
Answer(s): 63