Neave bought 220 silver and pink balloons for a party. The number of pink balloons was
47 times as many as the number of silver balloons. Neave used
13 times as many pink balloons as silver balloons and was left with twice as many pink balloons as silver balloons. How many balloons did Neave have in the end?
|
Pink (1) |
Silver (2) |
Make b the same. (2)x2 = (3) |
Before |
80 |
140 |
280 |
Change |
- 1 p |
- 3 p |
- 6 p |
After |
2 b |
1 b |
2 b |
Number of pink balloons that Neave bought at first = 4 u
Number of silver balloons that Neave bought at first = 7 u
Total number of balloons at first
= 4 u + 7 u
= 11 u
11 u = 220
1 u = 220 ÷ 11 = 20
Number of pink balloons at first
= 4 u
= 4 x 20
= 80
Number of silver balloons at first
= 7 u
= 7 x 20
= 140
80 - 1 p =
2 b --- (1)
140 - 3 p = 1 b --- (2)
(2)
x2
280 - 6 p =
2 b --- (3)
(3) = (1)
280 - 6 p = 80 - 1 p
6 p - 1 p = 280 - 80
5 p = 200
1 p = 200 ÷ 5 = 40
Number of balloons that Neave used
= 1 p + 3 p
= 4 p
= 4 x 40
= 160
Number of balloons that Neave had in the end
= 220 - 160
= 60
Answer(s): 60