15)
Given:
Balance in account A=-$5.42.
Balance in account B=-$35.76.
Taking the absolute value of the account balance, we get the magnitude of the overdrawn amount.
Hence, the magnitude of the overdrawn amount in account A is, 

 The magnitude of the overdrawn amount in account B is, 

Since the magnitude of the overdrawn amount is greater for account B, account B has the greater overdrawn.
16)
Balance in Account A=-$6.47.
Balance in Account B=-$2.56.

Since the absolute value of balance in account A is greater, account A has greater overdrawn. 
17)
Balance in Account A=-$32.56.
Balance in Account B=-$29.12.

Since the absolute value of account A is greater, account A has greater overdrawn.