Answer :
Since john pays back the amount of $120, then, the interest is known as Simple interest.
The Simple interest is the easiest method of calculating an interest rate on a loan.
- However, the compound interest is entails interest derived on a loan based on initial principal and the accumulated interest over period of time
Hence, since john pays back the amount of $120, then, the interest is known as Simple interest because the interest is not accumulated.
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