Emma bought a total of 30 big and small sweets. Then she decided to exchange 50% of her big sweets for the small ones in the ratio of 1 : 6. After the exchange, she had 45 sweets. What percentage of the sweets she bought were small ones?
| |
Big sweets |
Small sweets |
Total |
| Before |
2 u |
? |
30 |
| Change |
- 1 u |
|
|
Comparing big and
small sweets at exchange |
- 1 u |
+ 6 u |
+ 15 |
| After |
1 u |
? |
45 |
50% =
50100 =
12The number of big sweets that were exchanged for small sweets was repeated.
Number of extra sweets that Emma received due to the exchange
= 6 u - 1 u
= 5 u
5 u = 45 - 30
5 u = 15
1 u = 15 ÷ 5 = 3
Number of small sweets at first
= 30 - 2 u
= 30 - 2 x 3
= 30 - 6
= 24
Percentage of the sweets Emma bought that were small ones
=
2430 x 100%
= 80%
Answer(s): 80%
