Marion bought a total of 250 big and small jelly beans. Then she decided to exchange 20% of her big jelly beans for the small ones in the ratio of 1 : 3. After the exchange, she had 260 jelly beans. What percentage of the jelly beans she bought were small ones?
| |
Big jelly beans |
Small jelly beans |
Total |
| Before |
5 u |
? |
250 |
| Change |
- 1 u |
|
|
Comparing big and
small jelly beans at exchange |
- 1 u |
+ 3 u |
+ 10 |
| After |
4 u |
? |
260 |
20% =
20100 =
15The number of big jelly beans that were exchanged for small jelly beans was repeated.
Number of extra jelly beans that Marion received due to the exchange
= 3 u - 1 u
= 2 u
2 u = 260 - 250
2 u = 10
1 u = 10 ÷ 2 = 5
Number of small jelly beans at first
= 250 - 5 u
= 250 - 5 x 5
= 250 - 25
= 225
Percentage of the jelly beans Marion bought that were small ones
=
225250 x 100%
= 90%
Answer(s): 90%
