Tammy bought a total of 600 big and small jelly beans. Then she decided to exchange 40% of her big jelly beans for the small ones in the ratio of 2 : 7. After the exchange, she had 660 jelly beans. What percentage of the jelly beans she bought were small ones?
| |
Big jelly beans |
Small jelly beans |
Total |
| Before |
5 u |
? |
600 |
| Change |
- 2 u |
|
|
Comparing big and
small jelly beans at exchange |
- 2 u |
+ 7 u |
+ 60 |
| After |
3 u |
? |
660 |
40% =
40100 =
25The number of big jelly beans that were exchanged for small jelly beans was repeated.
Number of extra jelly beans that Tammy received due to the exchange
= 7 u - 2 u
= 5 u
5 u = 660 - 600
5 u = 60
1 u = 60 ÷ 5 = 12
Number of small jelly beans at first
= 600 - 5 u
= 600 - 5 x 12
= 600 - 60
= 540
Percentage of the jelly beans Tammy bought that were small ones
=
540600 x 100%
= 90%
Answer(s): 90%
