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


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Find the Principal When you Know the Interest, Rate, and Time
What amount of principal will earn interest of $175.50 at 6.5% in 8 months? Once again you can use the derive formula of I=Prt which becomes P = I/rt. Use the example above to help you. Remember, 8 months can be converted to days or, I can use 8/12 and move the 12 into the numerator in my formula.

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