Answer:
$20.96
Step-by-step explanation:
He has $638.54 in his account and writes a check for $159.50. The amount of money he needs to stay at or above $500 is denoted by x.
638.54 - 159.50 + x >= 500
After writing a check, Malcom has $479.04 left in his account, which is below his cutoff.
479.04 + x >= 500
He must add at least x amount of dollars to his account to avoid a fee.
x >= 20.96
In order to avoid a fee, Malcom must add a minimum of $20.96 to his account.
