Answer:
9.1%
Explanation:
Simple Interest = Principal × Rate × Time
First, converting R percent to r a decimal
r = R/100 = 7%/100 = 0.07 per year.
Solving our equation:
A = 18000(1 + (0.07 × 1)) = 19260
A = $19,260.00
I = A - P = $1,260.00
A = 13000(1 + (0.12 × 1)) = 14560
A = $14,560.00
I = A - P = $1,560.00
Total interest = $1,260.00 + $1,560.00
$ 2820
What average interest rate does he pay on the total $31,000 he owes? (Round your answer to the nearest tenth of a percent.)
Simple Interest = Principal × Rate × Time
Time = 1 years
Simple Interest = Total Interest = $2820
Principal = $31,000
Interest rate = Simple Interest/Principal
= $2820/$31,000
= 0.0909677419
0.0909677419 × 100
9.096774194%
Approximately to the nearest tenth of a percent = 9.1%