First week sells 6 chairs for $80 each. Next week, if chair is not sold, it will sell for 0.85 times previous week's price. Store needs to sell 6 chairs for total of $270 to make a profit. what is the last week in which all 6 chairs could be sold so that the store makes a profit?

Answer 1

The worst case is when all six chairs are sold at the lowest acceptable price, which is 270/6 = $45 each.

So, you want w where

80*0.85^w = 45
w = 3.54

So, the 3rd week is the last possible week to make a profit.

80*.85^3 = $49.13
80*.85^4 = $41.76 - too low