SOLUTION: this is a word problem....a certain amount of money saved for 1 year at a certain interest rate yielded $7.50. If the principal had been $25 more and the interest rate 1% less, the
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Question 461541: this is a word problem....a certain amount of money saved for 1 year at a certain interest rate yielded $7.50. If the principal had been $25 more and the interest rate 1% less, the interest would have been the same. find the principal and the rate. Answer by robertb(5830) (Show Source):
You can put this solution on YOUR website! It is given that (P + 25)(r - 0.01) = 7.50.
==> Pr - 0.01P + 25r - 0.25 = Pr
==> 25r - 0.01P = 0.25 ==> P = 2500r - 25
==> I = Pr = (2500r - 25)r = 7.50
==>
==>
Hence interest rate is 6%.
Pr = P*0.06 = 7.5 ==> P = 7.5/0.06 = $ 125.
