Sally would need 6 boxes, option B. If she's trying to reach 50, but already has 3 at home, then do 50-3=47. If there are 8 candy bars in a box, the closest basic multiple of 8 would be 6. 8 times 6 equals 48, which, obviously, is close to 47 (remember, you cannot have part of a box).
First let establish the eqautionlet y be the total costx is the number of orders y = 3x + 115 since the minimum order is 25x >= 25 then The school can spend a maximum of $800 800 <= 3x + 115 800 - 115 <= 3x685 <= 3x685/3 <= x228.33 <= x