Select the correct answerThe S.I. on a Sum of money will be Rs.600 after 10 years. If the Principal is tripled after 5 years, what will be the total interest at the end of 10th year?

The problem can be solved in the following steps:

Step 1: Understand the problem The problem states that the simple interest (S.I.) on a sum of money will be Rs.600 after 10 years. This means that the rate of interest is constant throughout the 10 years. However, the principal is tripled after 5 years, which means that for the first 5 years, the interest is calculated on the original principal, and for the next 5 years, the interest is calculated on three times the original principal.

Step 2: Calculate the interest for the first 5 years The interest for the first 5 years is half of the total interest for 10 years, which is Rs.600. Therefore, the interest for the first 5 years is Rs.600/2 = Rs.300.

Step 3: Calculate the interest for the next 5 years Since the principal is tripled after 5 years, the interest for the next 5 years will be three times the interest for the first 5 years. Therefore, the interest for the next 5 years is 3 * Rs.300 = Rs.900.

Step 4: Calculate the total interest The total interest at the end of the 10th year is the sum of the interest for the first 5 years and the interest for the next 5 years. Therefore, the total interest is Rs.300 + Rs.900 = Rs.1200.

So, the total interest at the end of the 10th year will be Rs.1200.