Isabella bought 70 pencils and Tommy bought 93 pencils. After Tommy used
35 times as many pencils as Isabella, he was left with four times as many pencils as Isabella. How many pencils did each of them have in the end?
- Isabella
- Tommy
| |
Make p the same.
(1)x4 = (3) |
Isabella
(1) |
Tommy
(2) |
| Before |
280 |
70 |
93 |
| Change |
- 20 u |
- 5 u |
- 3 u |
| After |
4 p |
1 p |
4 p |
(a)
70 - 5 u = 1 p --- (1)
93 - 3 u =
4 p --- (2)
(1)
x4
280 - 20 u =
4 p --- (3)
(3) = (2)
93 - 3 u = 280 - 20 u
20 u - 3 u = 280 - 93
17 u = 187
1 u = 187 ÷ 17 = 11
Number of pencils that Isabella had in the end
= 70 - 5 u
= 70 - 5 x 11
= 70 - 55
= 15
(b)
1 p = 15
Number of pencils that Tommy had in the end
= 4 p
= 4 x 15
= 60
Answer(s): (a) 15; (b) 60
