Simple interest: find the principal
Use interest = principal × rate × time, with the rate as a percent per year.
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A deposit at 2% simple interest per year earns $36 in 3 years. How much was deposited?
Answer: $600.00
A deposit at 2% simple interest per year earns $54 in 3 years. How much was deposited?
Answer: $900.00
A deposit at 5% simple interest per year earns $50 in 1 year. How much was deposited?
Answer: $1000.00
Tip: Use interest = principal × rate × time, with the rate as a percent per year.
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