PSLEAt first, Leah had a total of 121 green and grey balloons. 13 grey balloons burst. She then increased the number of green balloons by 90%. After that, Leah had a total of 180 balloons. How many grey balloons did she have at first?
|
Green |
Grey |
Total |
Before |
10 u |
|
121 |
Change |
+ 9 u |
- 13 |
+ 59 |
After |
19 u |
|
180 |
90100 =
910Increase in the number of balloons
= 180 - 121
= 59
9 u = 59 + 13
9 u = 72
1 u = 72 ÷ 9 = 8
Number of green balloons at first
= 10 u
= 10 x 8
= 80
Number of grey balloons at first
= 121 - 80
= 41
Answer(s): 41