Question

Sandeep borrowed ₹3000 for 4 years and ₹8000 for 2 integer1 upon 2 years from Sonia at the same rate of interest . The total interest earned by Sonia is ₹2800. Find the rate of interest.

Answer 1

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Here is your answer.

Let Rate of interest is r %
I case
SI = PRT/100
$= \frac{3000 \times 4 \times r}{100} \\ \\ = 120r$
II Case
SI = PRT/100
$= \frac{8000 \times 5 \times r}{2 \times 100} \\ \\ = 200r$
Total Interest is Rs 2800
ATQ
$120r + 200r = 2800 \\ \\ 320r = 2800 \\ \\ r = \frac{2800}{320} \\ \\ r = 8.75\%$
Therefore Rate of interest is 8.75%

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Answer 2

≡QUESTION≡

Sandeep borrowed ₹3000 for 4 years and ₹8000 for 2½ years from sonia at the same rate of interest. The total interest earned by sonia is ₹2800. Find the rate of interest.

                                                   

║⊕ANSWER⊕║

Simple Interest is : I = P * r * t / 100

(Where I = Interest

P = Principal Amount

r = Rate of Interest

t = Time period)

Sandeep had borrowed two times from Sonia

In the first case

P = Rs. 3000

r = ?

t = 4 years

In the second case

P =Rs.  8000

r = ?

t = 2.5 years  

The total interest earned by Sonia = Rs. 2880, while the rate of interest being same for both the cases.

S. I = P * r * t  / 100

$2880 = (3000 x r/100 x 4) + (8000 x r/100 x 2.5)\\2880 = 120r + 200r\\2880 = 320r\\r = 2880/320$

r = 9 %