
Answer:
Step-by-step explanation:
a) The amount of concern is ...
 (total interest)/(number of payments) = interest/payment
 $14,644.95/120 ≈ $122.04 . . . . amount of interest per payment
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b) The ratio of concern is ...
 (total interest)/(total payments) × 100% = 14,644.95/39,644.95 × 100%
 ≈ 36.94% . . . . percent of total payments that is interest