Seth and Ken had 63 pencils together. Ken had 3 less pencils than Seth. Both of them sold some of their pencils. Ken sold 40% more pencils than what Seth sold. In the end, Ken had half as many pencils left as Seth. How many pencils had Ken left?
| |
Seth
(1) |
Ken
(2) |
Make p the same
(2)x2 = (3) |
Comparing Seth
and Ken at first |
3 more |
|
|
| Before |
33 |
30 |
60 |
| Change |
- 5 u |
- 7 u |
- 14 u |
| After |
2 p |
1 p |
2 p |
Number of pencils that Ken had at first
= (63 - 3) ÷ 2
= 60 ÷ 2
= 30
Number of pencils that Seth had at first
= 30 + 3
= 33
Number of pencils that Ken sold in percent
= 100% + 40%
= 140%
140% =
140100 =
75 Make p the same.
(1) = (3)
33 - 5 u = 60 - 14 u
14 u - 5 u = 60 - 33
9 u = 27
1 u = 27 ÷ 9 = 3
Number of pencils that Ken had left
= 30 - 7 u
= 30 - 7 x 3
= 30 - 21
= 9
Answer(s): 9
