Noah bought 33 files and Archie bought 64 files. After Archie used
35 times as many files as Noah, he was left with four times as many files as Noah. How many files did each of them have in the end?
- Noah
- Archie
| |
Make p the same.
(1)x4 = (3) |
Noah
(1) |
Archie
(2) |
| Before |
132 |
33 |
64 |
| Change |
- 20 u |
- 5 u |
- 3 u |
| After |
4 p |
1 p |
4 p |
(a)
33 - 5 u = 1 p --- (1)
64 - 3 u =
4 p --- (2)
(1)
x4
132 - 20 u =
4 p --- (3)
(3) = (2)
64 - 3 u = 132 - 20 u
20 u - 3 u = 132 - 64
17 u = 68
1 u = 68 ÷ 17 = 4
Number of files that Noah had in the end
= 33 - 5 u
= 33 - 5 x 4
= 33 - 20
= 13
(b)
1 p = 13
Number of files that Archie had in the end
= 4 p
= 4 x 13
= 52
Answer(s): (a) 13; (b) 52
