Julian bought 55 notebooks and Riordan bought 70 notebooks. After Riordan used
27 times as many notebooks as Julian, he was left with thrice as many notebooks as Julian. How many notebooks did each of them have in the end?
- Julian
- Riordan
| |
Make p the same.
(1)x3 = (3) |
Julian
(1) |
Riordan
(2) |
| Before |
165 |
55 |
70 |
| Change |
- 21 u |
- 7 u |
- 2 u |
| After |
3 p |
1 p |
3 p |
(a)
55 - 7 u = 1 p --- (1)
70 - 2 u =
3 p --- (2)
(1)
x3
165 - 21 u =
3 p --- (3)
(3) = (2)
70 - 2 u = 165 - 21 u
21 u - 2 u = 165 - 70
19 u = 95
1 u = 95 ÷ 19 = 5
Number of notebooks that Julian had in the end
= 55 - 7 u
= 55 - 7 x 5
= 55 - 35
= 20
(b)
1 p = 20
Number of notebooks that Riordan had in the end
= 3 p
= 3 x 20
= 60
Answer(s): (a) 20; (b) 60
