PSLE The ratio of the number of jackets to that of skirts in a shopping centre was 11 : 7 in the end. After 20 skirts were sold, the ratio of the number of jackets to that of skirts became 3 : 1. What was the total number of jackets and skirts in the shopping centre in the end?
|
Jackets |
Skirts |
Total |
Before |
11x3 = 33 u |
7x3 = 21 u |
54 u |
Change |
|
- 20 |
|
After |
3x11 = 33 u |
1x11 = 11 u |
44 u |
The number of jackets remains unchanged.
Make the number of jackets the same.
LCM of 7 and 11 is 33.
Number of skirts sold
= 21 u - 11 u
= 10 u
1 u = 20 ÷ 10 = 2
Total number of jackets and skirts in the end
= 33 u + 11 u
= 44 u
= 44 x 2
= 88
Answer(s): 88