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Calculate Simple Interest, Principal, Rate or Time when 3 Values are Known


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What Annual Rate of Interest Is Needed for $2100.00 to earn $122.50 in 14 Mths?
When the amount of interest, the principal and the time period are known, you can use the derived formula from the simple interest formula to determine the rate. I=Prt becomes r=I/Pt. Remember to use 14/12 for time and move the 12 to the numerator in the formula above. Get your calculator and check to see if you're right.

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