Archie and Oliver had an equal number of books. Archie donated
17 of her books and Oliver donated
13 of his books. Oliver donated 28 more books than Archie. How many books did Oliver have at first?
| |
Archie |
Oliver |
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 Archie and Oliver each had at first is the same. Make the number of books that Archie and Oliver had at first the same. LCM of 7 and 3 is 21.
Number of books that Oliver donated more than Archie
= 7 u - 3 u
= 4 u
4 u = 28
1 u = 28 ÷ 4 = 7
Number of books that Oliver had
= 21 u
= 21 x 7
= 147
Answer(s): 147
