PSLEAt first, Leah had a total of 52 black and purple balloons. 18 purple balloons burst. She then increased the number of black balloons by 80%. After that, Leah had a total of 42 balloons. How many purple balloons did she have at first?
|
Black |
Purple |
Total |
Before |
5 u |
|
52 |
Change |
+ 4 u |
- 18 |
- 10 |
After |
9 u |
|
42 |
80100 =
45Decrease in the number of balloons
= 52 - 42
= 10
4 u = 18 - 10
4 u = 8
1 u = 8 ÷ 4 = 2
Number of black balloons at first
= 5 u
= 5 x 2
= 10
Number of purple balloons at first
= 52 - 10
= 42
Answer(s): 42