PSLE The ratio of the number of jackets to that of coats in a shop was 7 : 2 at first. After 30 coats were sold, the ratio of the number of jackets to that of coats became 6 : 1. What was the total number of jackets and coats in the shop at first?
|
Jackets |
Coats |
Total |
Before |
7x6 = 42 u |
2x6 = 12 u |
54 u |
Change |
|
- 30 |
|
After |
6x7 = 42 u |
1x7 = 7 u |
49 u |
The number of jackets remains unchanged.
Make the number of jackets the same.
LCM of 2 and 7 is 42.
Number of coats sold
= 12 u - 7 u
= 5 u
1 u = 30 ÷ 5 = 6
Total number of jackets and coats at first
= 42 u + 12 u
= 54 u
= 54 x 6
= 324
Answer(s): 324