Answer:
$6.6
Step-by-step explanation:
Let's find out what his balance is after those transactions.
Initial balance: 126.50
After bill:
126.50 - 87.21 = 39.29
After breakfast:
39.29 - 5.64 = 33.65
After deposit (we're adding money now!):
33.65 + 15 = 48.65
After 2nd bill:
48.65 - 55.25 = -6.6
We find that his balance is negative $6.6. Thus, to get to $0, he needs to deposit an additional $6.6.
Answer: $6.6