Mary bought five times as many wafers as Cole. After Mary ate 3 wafers, she had 9 more wafers than Cole. How many wafers did they buy altogether?
| |
Mary |
Cole |
Total |
| Before |
5 u |
1 u |
6 u |
| Change |
- 3 |
|
|
| After |
5 u - 3 |
1 u |
|
The number of wafers that Cole had remains unchanged.
If Cole had another 9 wafers in the end, the number of wafers that Mary and Cole had would be the same.
5 u - 3 = 1 u + 9
5 u - 1 u = 9 + 3
4 u = 12
1 u = 12 ÷ 4 = 3
Total number of wafers
= 5 u + 1 u
= 6 u
= 6 x 3
= 18
Answer(s): 18
