Interest rate problem

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by sudhir3127 » Sat Jul 26, 2008 5:12 am
my Answer is 8d/3

here it goes...

(d * k*2 )/100= 600 .... I ( simple interest = (principal* rate*time)/100)

2dk = 60000
dk = 30000 ( u can ignore the zeros as well)
k= 30000/d

(d*K* 3)/100 = 2400
dk = 80000 ----------------------- II

K= 30000/d*8/3d = 80000
which is equation 2

hence the answer is 8d/3

Use can use plugging in as well..( easier way)

interest is 600 for 2 yrs ..

Assume d = 10000 ( principal)
rate = 3%

in the second case

(d1* 3* 3)/ 100 = 2400

hence d1 = 80000/ 3 = 8d /3

Hope its clear

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by dbart06 » Sat Jul 26, 2008 7:24 am
why do you keep dividing by 100.
simple interest formula is : int=prin * int * time
Where is the 100 coming from?

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by nitingupta5 » Sat Jul 26, 2008 7:26 am
Answer 8d/3

SI =(principal*rate*time)/100

Assume the new principal as P

600= (d*k*2)/100
k = 60000/2d -----(1)

2400 = P * (60000/2d)*3/100 Using the same rate in terms of d

P = 8d/3

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by dbart06 » Sat Jul 26, 2008 7:48 am
Still not clear where you are getting the 100. I have looked at the formula and do not see where you divide by 100.

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by dbart06 » Sat Jul 26, 2008 7:51 am
Never mind. You are writing the formula in a different way. You are dividing by 100 to express the percent. Sorry!

Sometimes its hard to understand the flow of how people explain things.