Victoria bought a total of 20 big and small sweets. Then she decided to exchange 50% of her big sweets for the small ones in the ratio of 1 : 3. After the exchange, she had 28 sweets. What percentage of the sweets she bought were small ones?
|
Big sweets |
Small sweets |
Total |
Before |
2 u |
? |
20 |
Change |
- 1 u |
|
|
Comparing big and small sweets at exchange |
- 1 u |
+ 3 u |
+ 8 |
After |
1 u |
? |
28 |
50% =
50100 =
12The number of big sweets that were exchanged for small sweets was repeated.
Number of extra sweets that Victoria received due to the exchange
= 3 u - 1 u
= 2 u
2 u = 28 - 20
2 u = 8
1 u = 8 ÷ 2 = 4
Number of small sweets at first
= 20 - 2 u
= 20 - 2 x 4
= 20 - 8
= 12
Percentage of the sweets Victoria bought that were small ones
=
1220 x 100%
= 60%
Answer(s): 60%