Penelope bought a total of 200 big and small chocolate bars. Then she decided to exchange 75% of her big chocolate bars for the small ones in the ratio of 3 : 8. After the exchange, she had 240 chocolate bars. What percentage of the chocolate bars she bought were small ones?
|
Big chocolate bars |
Small chocolate bars |
Total |
Before |
4 u |
? |
200 |
Change |
- 3 u |
|
|
Comparing big and small chocolate bars at exchange |
- 3 u |
+ 8 u |
+ 40 |
After |
1 u |
? |
240 |
75% =
75100 =
34The number of big chocolate bars that were exchanged for small chocolate bars was repeated.
Number of extra chocolate bars that Penelope received due to the exchange
= 8 u - 3 u
= 5 u
5 u = 240 - 200
5 u = 40
1 u = 40 ÷ 5 = 8
Number of small chocolate bars at first
= 200 - 4 u
= 200 - 4 x 8
= 200 - 32
= 168
Percentage of the chocolate bars Penelope bought that were small ones
=
168200 x 100%
= 84%
Answer(s): 84%