Answer:
check the explanation
Step-by-step explanation:
the step by step calculation to the question above can be seen below:
Estimated coupons to be redeemed 611740 =838000*73%
Less: Coupons redeemed 262000 
Coupons unredeemed 349740 
X Cost per Coupon 4.50 
Liability for unredeemed Coupons 1573830