# A Sum Becomes its Double in 10 Years. Find the Annual Rate of simple Interest.

**Answer: (3) 10 %**

**Explanation:-**

Let the principal is Rs.X and rate = R

Then, Amount = 2 X

Simple interest = 2 X – X = X

**Formula-**

**Simple Interest = P x R x T/100**

**Where, P = principal , R = rate, & T = time.**

Then,

X = X x R x 10/100

1 = R / 10

R = 10 % .

Then, the rate is 10 %.

Hence, the answer is (3) 10 %.