PSLEAt first, Leah had a total of 89 black and brown balloons. 14 brown balloons burst. She then increased the number of black balloons by 90%. After that, Leah had a total of 120 balloons. How many brown balloons did she have at first?
|
Black |
Brown |
Total |
Before |
10 u |
|
89 |
Change |
+ 9 u |
- 14 |
+ 31 |
After |
19 u |
|
120 |
90100 =
910Increase in the number of balloons
= 120 - 89
= 31
9 u = 31 + 14
9 u = 45
1 u = 45 ÷ 9 = 5
Number of black balloons at first
= 10 u
= 10 x 5
= 50
Number of brown balloons at first
= 89 - 50
= 39
Answer(s): 39