Jack and Reggie had 113 files together. Jack had 11 more files than Reggie. Both of them sold some of their files. Reggie sold 10% less files than what Jack sold. In the end, Reggie had half as many files left as Jack. How many files had Jack left?
| |
Jack
(1) |
Reggie
(2) |
Make p the same
(2)x2 = (3) |
Comparing Jack
and Reggie at first |
11 more |
|
|
| Before |
62 |
51 |
102 |
| Change |
- 10 u |
- 9 u |
- 18 u |
| After |
2 p |
1 p |
2 p |
Number of files that Reggie had at first
= (113 - 11) ÷ 2
= 102 ÷ 2
= 51
Number of files that Jack had at first
= 51 + 11
= 62
Number of files that Reggie sold in percent
= 100% - 10%
= 90%
90% =
90100 =
910 Make p the same.
(1) = (3)
62 - 10 u = 102 - 18 u
18 u - 10 u = 102 - 62
8 u = 40
1 u = 40 ÷ 8 = 5
Number of files that Jack had left
= 62 - 10 u
= 62 - 10 x 5
= 62 - 50
= 12
Answer(s): 12
