Question

If Rs. 4 becomes Rs. 10 in 50 years at simple interest, the rate % p.a. is

Answer 1

Answer:

3%

Step-by-step explanation:

here,

principle=4rs

simple interest=A-P=10-4=6rs

SI=PNR/100

6=4*50*R/100

R=3%

Answer 2

Given: Principal = Rs. 4

           Amount = Rs. 10

           Time = 50 years

To find: The rate of interest

Let: Rate of interest be $R$

Solution:

∵ $Amount = Principal + Simple \ Interest$

and  $Simple \ Interest = \frac{Principal * Rate * Time}{100}$

⇒ $Amount = Principal + \frac{Principal* Rate * Time}{100}$

⇒ $10 = 4 + \frac{4 * R * 50}{100} = 4 + \frac{200R}{100}$

⇒ $10 = \frac{400 \ + \ 200R}{100}$

⇒ $10*100 = 400 + 200R$

⇒ $200R = 1000 - 400 = 600$

⇒ $R = \frac{600}{200} = 3$

Hence, rate of interest R is 3% p.a.