Lucy bought 75 staplers and Gabriel bought 90 staplers. After Gabriel used
27 times as many staplers as Lucy, he was left with twice as many staplers as Lucy. How many staplers did each of them have in the end?
- Lucy
- Gabriel
| |
Make p the same.
(1)x2 = (3) |
Lucy
(1) |
Gabriel
(2) |
| Before |
150 |
75 |
90 |
| Change |
- 14 u |
- 7 u |
- 2 u |
| After |
2 p |
1 p |
2 p |
(a)
75 - 7 u = 1 p --- (1)
90 - 2 u =
2 p --- (2)
(1)
x2
150 - 14 u =
2 p --- (3)
(3) = (2)
90 - 2 u = 150 - 14 u
14 u - 2 u = 150 - 90
12 u = 60
1 u = 60 ÷ 12 = 5
Number of staplers that Lucy had in the end
= 75 - 7 u
= 75 - 7 x 5
= 75 - 35
= 40
(b)
1 p = 40
Number of staplers that Gabriel had in the end
= 2 p
= 2 x 40
= 80
Answer(s): (a) 40; (b) 80
