Paul and Ken had an equal number of books. Paul donated
17 of her books and Ken donated
13 of his books. Ken donated 8 more books than Paul. How many books did Ken have at first?
| |
Paul |
Ken |
Before
|
7x3 =
21 u |
3x7 =
21 u |
Change
|
- 1x3 =
- 3 u |
- 1x7 =
- 7 u |
After
|
6x3 =
18 u |
2x7 =
14 u |
The number of books that Paul and Ken each had at first is the same. Make the number of books that Paul and Ken had at first the same. LCM of 7 and 3 is 21.
Number of books that Ken donated more than Paul
= 7 u - 3 u
= 4 u
4 u = 8
1 u = 8 ÷ 4 = 2
Number of books that Ken had
= 21 u
= 21 x 2
= 42
Answer(s): 42
