Your sister is selling Girl Scout cookies that cost $3.50 per box. Your family bought 6 boxes. How many more boxes of
cookies does your sister need to sell to raise $196?
So since she needs $196 and per box it would be $3.50 and 6 boxes is $21 total, she would need to sell 56 boxes total to get to her goal, but since her parents bought 6 boxes already she will only need 50 more.
