To be able to determine which among the coupon gives a lower price, let's determine what is 45% of $73 so that we could compare it with the $30 rebate. The highest amount among the two coupons will give you a lower price.
Let's determinte the 45% of 73:
Coupon A gives you $32.85 dollar off of a $73 Jacket.
Coupon A will give you a lower price compared to Coupon B. The price of the jacket will be $2.85 lesser than using Coupon B.