Carl bought some pastries. He bought some biscuits with $7.70 more than half his money. He then bought some puffs with $3.70 less than half of his remaining money. He then had $10.80 left. How much did he pay for the biscuits?
| Biscuits |
Remaining amount |
| 1 u + $7.70 |
1 u - $7.70 |
| |
Puffs |
Left |
| |
1 p - $3.70 |
1 p + $3.70 |
| |
|
$10.80 |
Working backwards.
Amount that Carl had left = 1 p + 3.70
1 p + 3.70 = 10.80
1 p = 10.80 - 3.70 = 7.10
Remaining amount after he bought some biscuits
= 2 p
= 2 x 7.10
= $14.20
Remaining amount after he bought some biscuits = 1 u - 7.70
1 u - 7.70 = 14.20
1 u = 14.20 + 7.70
1 u = 21.90
Amount that Carl spent on some biscuits
= 1 u + 7.70
= 21.90 + 7.70
= $29.60
Answer(s): $29.60
