Risa bought four times as many cupcakes as Paul. After Risa ate 7 cupcakes, she had 8 more cupcakes than Paul. How many cupcakes did they buy altogether?
| |
Risa |
Paul |
Total |
| Before |
4 u |
1 u |
5 u |
| Change |
- 7 |
|
|
| After |
4 u - 7 |
1 u |
|
The number of cupcakes that Paul had remains unchanged.
If Paul had another 8 cupcakes in the end, the number of cupcakes that Risa and Paul had would be the same.
4 u - 7 = 1 u + 8
4 u - 1 u = 8 + 7
3 u = 15
1 u = 15 ÷ 3 = 5
Total number of cupcakes
= 4 u + 1 u
= 5 u
= 5 x 5
= 25
Answer(s): 25
