Below is an instruction that describes a task. Write a response that appropriately completes the request in English. Please answer in English.

### Instruction:
The card shop has two boxes of cards. The first box contains cards that cost $1.25 each. The second box contains cards that cost $1.75 each. A boy then comes in and buys 6 cards from each box. What was the total cost, in dollars, of the cards he bought?

### Response:
The cost of one card from each box in total is 1.25+1.75=<<1.25+1.75=3>>3 dollars
The boy buys 6 cards from each box, bringing the total cost to 3*6=<<6*3=18>>18 dollars.
#### 18