Barbara bought thrice as many tarts as Albert. After Barbara ate 6 tarts, she had 12 more tarts than Albert. How many tarts did they buy altogether?
| |
Barbara |
Albert |
Total |
| Before |
3 u |
1 u |
4 u |
| Change |
- 6 |
|
|
| After |
3 u - 6 |
1 u |
|
The number of tarts that Albert had remains unchanged.
If Albert had another 12 tarts in the end, the number of tarts that Barbara and Albert had would be the same.
3 u - 6 = 1 u + 12
3 u - 1 u = 12 + 6
2 u = 18
1 u = 18 ÷ 2 = 9
Total number of tarts
= 3 u + 1 u
= 4 u
= 4 x 9
= 36
Answer(s): 36
