Ryan bought 120 yellow and grey balloons for a party. The number of grey balloons was
35 times as many as the number of yellow balloons. Ryan used
14 times as many grey balloons as yellow balloons and was left with twice as many grey balloons as yellow balloons. How many balloons did Ryan have in the end?
|
Grey (1) |
Yellow (2) |
Make b the same. (2)x2 = (3) |
Before |
45 |
75 |
150 |
Change |
- 1 p |
- 4 p |
- 8 p |
After |
2 b |
1 b |
2 b |
Number of grey balloons that Ryan bought at first = 3 u
Number of yellow balloons that Ryan bought at first = 5 u
Total number of balloons at first
= 3 u + 5 u
= 8 u
8 u = 120
1 u = 120 ÷ 8 = 15
Number of grey balloons at first
= 3 u
= 3 x 15
= 45
Number of yellow balloons at first
= 5 u
= 5 x 15
= 75
45 - 1 p =
2 b --- (1)
75 - 4 p = 1 b --- (2)
(2)
x2
150 - 8 p =
2 b --- (3)
(3) = (1)
150 - 8 p = 45 - 1 p
8 p - 1 p = 150 - 45
7 p = 105
1 p = 105 ÷ 7 = 15
Number of balloons that Ryan used
= 1 p + 4 p
= 5 p
= 5 x 15
= 75
Number of balloons that Ryan had in the end
= 120 - 75
= 45
Answer(s): 45