**To Find Principal**

__When interest, time, rate are given:__

__Example 01__**:**

What amount was borrowed, for which amount of interest is 200 at the rate of 5% for 4 years.

__Solution__**:**

Let P = Principal , Rate = 5%, Interest = 200, time = *n* = 4, I = Interest

We know that

**To Find Principal**

__When amount, rate, time are given:__

__Example 02__**:**

If the amount for 2 years at 6% is 4,000, what was the principal?

__Solution__**:**

Let P = Principal, Rate = 6%, *n* = 2, A = 4,000

We know that

**To Find Rate**

__When interest, time, principal are given:__

__Example 03__**:**

The amount of simple interest for Rs.15,000 for 2 years is 1000, find rate of interest.

__Solution__**:**

Let Principal = 15,000, Simple interest = I = 1000, Time = 2 years

Interest = P r *n*