Final answer:
After making a down payment of $106.40, Ivanna will need to pay the remaining balance of $319.60 in 4 equal installments, which amounts to $79.90 per installment.
Step-by-step explanation:
Ivanna needs to calculate the amount for each installment after her down payment on the refrigerator. First, let's subtract the down payment from the total cost of the refrigerator:
Total cost of refrigerator = $426
Down payment = $106.40
Remaining balance = Total cost - Down payment = $426 - $106.40 = $319.60
Now, to find the cost per installment, divide the remaining balance by the number of installments:
Number of installments = 4
Cost per installment = Remaining balance ÷ Number of installments = $319.60 ÷ 4 = $79.90
Therefore, Ivanna will need to pay $79.90 per installment.