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