Question

At a certain rate of simple interest, Rs.4050 amounts upto Rs.4526.50 in 2 years. At the same rate of simple interest, how much would 1 lakh amount in 3 years.

Answer 1

Let interest be i per annum simple interest.
4050(1+i*2)=4526.50
solve for i.
1+i*2=4526.5/4050=1.117654321
i=(1.117654321-1)/2
=0.058827

1 lakh = 100,000
So after 3 years, accumulated amount
=100,000(1+3i)
=100,000(1.1764815)
=117648.15

Answer 2

4526.5/4050 = 1.1176 or 11.76% in two years.

That means it gets 5.88% each year

so, 1 lakh grows by 0.0588 each year
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