In how many years, an amount becomes three times of itself, if simple interest is calculated at a rate of 10% per annum?

20

Let principal = P

Sum become 3 times of itself.  So , Amount = 3P

Simple interest = 3P - P = 2P

We know ,

Simple Interest = \(\frac{Principal ×Rate × Time }{100}\)

2P = \(\frac{P ×10× Time }{100}\)

Time = 20 years