PSLEAt first, Leah had a total of 51 yellow and red balloons. 20 red balloons burst. She then increased the number of yellow balloons by 70%. After that, Leah had a total of 45 balloons. How many red balloons did she have at first?
|
Yellow |
Red |
Total |
Before |
10 u |
|
51 |
Change |
+ 7 u |
- 20 |
- 6 |
After |
17 u |
|
45 |
70100 =
710Decrease in the number of balloons
= 51 - 45
= 6
7 u = 20 - 6
7 u = 14
1 u = 14 ÷ 7 = 2
Number of yellow balloons at first
= 10 u
= 10 x 2
= 20
Number of red balloons at first
= 51 - 20
= 31
Answer(s): 31