A bond/warrant package is priced to sell at a face value of $1,000. Each bond comes with 50 detachable warrants. A warrant gives the owner the right to buy one share of stock at $20 per share. The value of a warrant has been estimated at $2. The bonds mature in 20 years. Similar bonds without warrants yield 10 percent. What is the bond's annual coupon rate?

I know the answer is $88.25. Can someone show me the steps to get this answer? Thank you!