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Volkaroar
Jan 31, 2012, 06:56 PM
How much must be placed in a five-month term deposit earning 4.1% simple interest in order to earn $500 interest?

I realize that the formula here would be s = P(1 rt), which rearranged to solve for P would be P = S/(1 rt) but when I input the numbers to solve for P I always get the wrong answer apparently. Am I using the right equation or no?

ArcSine
Feb 1, 2012, 04:39 AM
In a simple-interest scenario the total interest earned is the product of the Principle, the Rate, and the total Time. So for this one your set-up is

500 = P x r x t

You're given r and t, so just solve that one for P. Remember that since r is given as an annual rate, your t will have to be 5 / 12.