Owen and Elijah had 117 pens together. Owen had 17 more pens than Elijah. Both of them sold some of their pens. Elijah sold 20% less pens than what Owen sold. In the end, Elijah had half as many pens left as Owen. How many pens had Owen left?
| |
Owen
(1) |
Elijah
(2) |
Make p the same
(2)x2 = (3) |
Comparing Owen
and Elijah at first |
17 more |
|
|
| Before |
67 |
50 |
100 |
| Change |
- 5 u |
- 4 u |
- 8 u |
| After |
2 p |
1 p |
2 p |
Number of pens that Elijah had at first
= (117 - 17) ÷ 2
= 100 ÷ 2
= 50
Number of pens that Owen had at first
= 50 + 17
= 67
Number of pens that Elijah sold in percent
= 100% - 20%
= 80%
80% =
80100 =
45 Make p the same.
(1) = (3)
67 - 5 u = 100 - 8 u
8 u - 5 u = 100 - 67
3 u = 33
1 u = 33 ÷ 3 = 11
Number of pens that Owen had left
= 67 - 5 u
= 67 - 5 x 11
= 67 - 55
= 12
Answer(s): 12
