Will and Ben had 84 pencils together. Ben had 4 less pencils than Will. Both of them sold some of their pencils. Ben sold 10% more pencils than what Will sold. In the end, Ben had half as many pencils left as Will. How many pencils had Ben left?
| |
Will
(1) |
Ben
(2) |
Make p the same
(2)x2 = (3) |
Comparing Will
and Ben at first |
4 more |
|
|
| Before |
44 |
40 |
80 |
| Change |
- 10 u |
- 11 u |
- 22 u |
| After |
2 p |
1 p |
2 p |
Number of pencils that Ben had at first
= (84 - 4) ÷ 2
= 80 ÷ 2
= 40
Number of pencils that Will had at first
= 40 + 4
= 44
Number of pencils that Ben sold in percent
= 100% + 10%
= 110%
110% =
110100 =
1110 Make p the same.
(1) = (3)
44 - 10 u = 80 - 22 u
22 u - 10 u = 80 - 44
12 u = 36
1 u = 36 ÷ 12 = 3
Number of pencils that Ben had left
= 40 - 11 u
= 40 - 11 x 3
= 40 - 33
= 7
Answer(s): 7
