Question

3. A sum of 3200 becomes *3456 in two years at a certain rate of simple interest. What is the rate of
interest per annum?
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Answer 1

Given : -

• Amount = Rs.3456
• Principal = Rs.3200
• Time = 2 years

To Find : -

• Rate of interest

Solution : -

As we know that

→ Amount = Principal + Simple interest

→ Simple interest = Amount - Principal

→ Simple interest = 3456 - 3200

→ Simple interest = Rs.256

According to the question

→ Simple interest = P × R × T/100

→ 256 = 3200 × R × 2/100

→ 256 = 64 × R

→ R = 256/64

→ R = 4%

Hence,

• Rate of interest = 4%

Answer 2

Answer:

The rate will  be 4%

Step-by-step explanation:

Let the rate of S.I. be r

Given,

Sum(Principal) = Rs. 3200

Time = 2 years

S.I. = 256 (difference between 3456 and 3200 as 3456 comes after adding the S.I. to the sum 3200)

(3200 X r X 2)/100 = 256

32 X r X 2 = 256

64 X r = 256

r = 256/64

r = 4

So, the rate is 4% per annum