Deanna is selling Gal Scout cookies. Her goal is to sell an average of $90 worth of cookies each day for the next 10 days. If each box of cookies costs $2.25, and she sold an average of 44 boxes a day for the first 6 days, how many boxes must she sell, on average, for the last four days if she is to reach her goal?

90 - 6(2.25)(44) = amount needed

Amount needed/(4*2.25) = average boxes that need to be sold.