Question

The difference between si and ci is 2 years on the same sum and at the same rate of interest, compound annually is The difference between si and ci for 3 years on the same sum and at the same rate of interest is Rs.3294.Find the rate of interest
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Answer 1

Answer:

T=2years, R=5%p.a,

CI−SI=Rs5

Let the sum of money lent be x.

Then,

Simple Interest=Rs

100

x×2×5

=Rs

10

x

Compound Interest:-

Interest for the 1st year=Rs

100

x×5×1

=Rs

20

x

Amount after the 1st year=Rs x+

20

x

=Rs

20

21x

Interest for the 2nd year=Rs

20

21x

×

100

5×1

=Rs

400

21x

Amount after the 2nd year=Rsx+

400

21x

+

20

21x

=Rs

400

441

Then,

400

41x

−

10

x

=5

⇒

400

41x−40x

=5

⇒x=Rs 2000

∴Required sum of money lent=Rs2000.