Step-by-step explanation
Given:
Principal (Initial amount) = $4, 500
Time = 6 years
If she paid $139.15 in each month, and there are 12 months in a year, this implies that she paid 139.15 x 12 = $1669.8 in 1 year
Amount paid in 6 years = $1669.8 x 6 = $10018.8
Hence, the total amount paid = $10018.8
To find the interest,
Amount = Principal + interest
From the above,
Interest = Amount - Principal
= $10018.80 - $4500
= $5518.8