A man invested 6000 for 4 years in a simple rate of 9% per annum. what is his amount at the end of the four years?
The formula for simple interest is I = P * r * t, where I is the interest, P is the principal (initial amount), r is the rate, and t is the time in years.
Using this formula, we can calculate the interest earned by the man over 4 years:
I = 6000 * 0.09 * 4
I = 2160
Therefore, the man earned 2160 in interest over 4 years, and his total amount at the end of the four years is the sum of his initial investment and the interest earned:
Total amount = 6000 + 2160
Total amount = 8160
So, the man's amount at the end of the four years is 8160.