Prior to makting deposits of $75 and $50, Marian had a balance of $ 102 in her checking account.
How much must she deposits so that her balance
will be at least $300 and she can avoid service fee?

  $73

Step-by-step explanation:

The additional amount Marian needs to add to her account is ...

  $300 -102 -75 -50 = $73

Comment on service fee

Marian can also avoid an account service fee by changing her checking account to a credit union instead of a bank. (A credit union may require a $5 minimum savings account balance.)