Question

Sandeep borrowed ₹3000 for4 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 1

≡QUESTION≡

Sandeep borrowed ₹3000 for4 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 %