Caleb bought 39 staplers and Justin bought 81 staplers. After Justin used
35 times as many staplers as Caleb, he was left with thrice as many staplers as Caleb. How many staplers did each of them have in the end?
- Caleb
- Justin
| |
Make p the same.
(1)x3 = (3) |
Caleb
(1) |
Justin
(2) |
| Before |
117 |
39 |
81 |
| Change |
- 15 u |
- 5 u |
- 3 u |
| After |
3 p |
1 p |
3 p |
(a)
39 - 5 u = 1 p --- (1)
81 - 3 u =
3 p --- (2)
(1)
x3
117 - 15 u =
3 p --- (3)
(3) = (2)
81 - 3 u = 117 - 15 u
15 u - 3 u = 117 - 81
12 u = 36
1 u = 36 ÷ 12 = 3
Number of staplers that Caleb had in the end
= 39 - 5 u
= 39 - 5 x 3
= 39 - 15
= 24
(b)
1 p = 24
Number of staplers that Justin had in the end
= 3 p
= 3 x 24
= 72
Answer(s): (a) 24; (b) 72
