You are shopping for a video game system.
A - $162 | 40% Markup
B - $155 | 30% Markup
C - $160 | 25% Markup

a. At which store should you buy the system?
A, B, or C?

b. Store A has a weekend sale. To the nearest hundredth of a percent, what discount must store A offer for you to buy the system there?

Store A must offer at least a __% discount.