Mary bought a total of 360 big and small lollipops. Then she decided to exchange 30% of her big lollipops for the small ones in the ratio of 3 : 7. After the exchange, she had 396 lollipops. What percentage of the lollipops she bought were small ones?
| |
Big lollipops |
Small lollipops |
Total |
| Before |
10 u |
? |
360 |
| Change |
- 3 u |
|
|
Comparing big and
small lollipops at exchange |
- 3 u |
+ 7 u |
+ 36 |
| After |
7 u |
? |
396 |
30% =
30100 =
310The number of big lollipops that were exchanged for small lollipops was repeated.
Number of extra lollipops that Mary received due to the exchange
= 7 u - 3 u
= 4 u
4 u = 396 - 360
4 u = 36
1 u = 36 ÷ 4 = 9
Number of small lollipops at first
= 360 - 10 u
= 360 - 10 x 9
= 360 - 90
= 270
Percentage of the lollipops Mary bought that were small ones
=
270360 x 100%
= 75%
Answer(s): 75%
