Given:
A student has $78 in his checking account.
The student spends $12 on lunch.
To find:
The number that could be combined with the amount left in the account to make zero.
Solution:
We have,
Amount in account = $78
Money spend on lunch = $12
Remaining amount = Amount in account - Money spend on lunch
= $78 - $12
= $66
Remaining amount is $66. So, -66 could be combined with the amount left in the account to make zero.
[tex]66+(-66)=66-66=0[/tex]
Therefore, the correct option is C.
