PSLE The ratio of the number of sweaters to that of dresses in a boutique was 3 : 1 at first. After 10 dresses were sold, the ratio of the number of sweaters to that of dresses became 11 : 3. What was the total number of sweaters and dresses in the boutique at first?
|
Sweaters |
Dresses |
Total |
Before |
3x11 = 33 u |
1x11 = 11 u |
44 u |
Change |
|
- 10 |
|
After |
11x3 = 33 u |
3x3 = 9 u |
42 u |
The number of sweaters remains unchanged.
Make the number of sweaters the same.
LCM of 1 and 3 is 33.
Number of dresses sold
= 11 u - 9 u
= 2 u
1 u = 10 ÷ 2 = 5
Total number of sweaters and dresses at first
= 33 u + 11 u
= 44 u
= 44 x 5
= 220
Answer(s): 220