Which answer best describes how to solve this story problem? a local store plans to put three coupons in each mailbox on a street. the right side of the street has 16 mailboxes. the left side of the street has 17 mailboxes. how many coupons is the local store putting in mailboxes? a. multiply 16 by 17. add 3 to the product. b. multiply 16 by 3. multiply 17 by 3. add the products. c. add 16 and 3. add 17 and 3. multiply the sums.