Zane and Mark had 45 pencils together. Zane had 11 more pencils than Mark. Both of them sold some of their pencils. Mark sold 25% less pencils than what Zane sold. In the end, Mark had half as many pencils left as Zane. How many pencils had Zane left?
| |
Zane
(1) |
Mark
(2) |
Make p the same
(2)x2 = (3) |
Comparing Zane
and Mark at first |
11 more |
|
|
| Before |
28 |
17 |
34 |
| Change |
- 4 u |
- 3 u |
- 6 u |
| After |
2 p |
1 p |
2 p |
Number of pencils that Mark had at first
= (45 - 11) ÷ 2
= 34 ÷ 2
= 17
Number of pencils that Zane had at first
= 17 + 11
= 28
Number of pencils that Mark sold in percent
= 100% - 25%
= 75%
75% =
75100 =
34 Make p the same.
(1) = (3)
28 - 4 u = 34 - 6 u
6 u - 4 u = 34 - 28
2 u = 6
1 u = 6 ÷ 2 = 3
Number of pencils that Zane had left
= 28 - 4 u
= 28 - 4 x 3
= 28 - 12
= 16
Answer(s): 16
