Answer:
$4.90
Explanation:
He already has $13.70 (7.40+6.30) saved up so you have to subtract that from 18.60 to find the total Ace needs to save up.
18.60-13.70=4.90
To check your answer, you can add 7.40, 6.30, and 4.90 and see if you get a total of 18.60.
Check: 7.40+6.30+4.90=18.60