Ethan and Elijah had 105 files together. Elijah had 3 less files than Ethan. Both of them sold some of their files. Elijah sold 10% more files than what Ethan sold. In the end, Elijah had half as many files left as Ethan. How many files had Elijah left?
| |
Ethan
(1) |
Elijah
(2) |
Make p the same
(2)x2 = (3) |
Comparing Ethan
and Elijah at first |
3 more |
|
|
| Before |
54 |
51 |
102 |
| Change |
- 10 u |
- 11 u |
- 22 u |
| After |
2 p |
1 p |
2 p |
Number of files that Elijah had at first
= (105 - 3) ÷ 2
= 102 ÷ 2
= 51
Number of files that Ethan had at first
= 51 + 3
= 54
Number of files that Elijah sold in percent
= 100% + 10%
= 110%
110% =
110100 =
1110 Make p the same.
(1) = (3)
54 - 10 u = 102 - 22 u
22 u - 10 u = 102 - 54
12 u = 48
1 u = 48 ÷ 12 = 4
Number of files that Elijah had left
= 51 - 11 u
= 51 - 11 x 4
= 51 - 44
= 7
Answer(s): 7
