PSLEAt first, Leah had a total of 56 blue and black balloons. 18 black balloons burst. She then increased the number of blue balloons by 80%. After that, Leah had a total of 54 balloons. How many black balloons did she have at first?
|
Blue |
Black |
Total |
Before |
5 u |
|
56 |
Change |
+ 4 u |
- 18 |
- 2 |
After |
9 u |
|
54 |
80100 =
45Decrease in the number of balloons
= 56 - 54
= 2
4 u = 18 - 2
4 u = 16
1 u = 16 ÷ 4 = 4
Number of blue balloons at first
= 5 u
= 5 x 4
= 20
Number of black balloons at first
= 56 - 20
= 36
Answer(s): 36