A certain sum was invested on simple interest for a period of seven years. During the period of the sixth and the seventh years combined, the interest earned was rs. 292. If the maturity amount is rs. 3,942, then what is the rate percentage of the interest?

A) 6.25%
B) 2.5%
C) 2%
D) 5%

OOOH My BAD. I missed where it said simple interest

You must have seen my mistake - your answer of 5% is correct.

To find the rate percentage of interest, we need to determine the rate at which the investment is earning interest over the period of seven years.

Let's assume the principal amount (the initial investment) is P, and the rate of interest is R%.

Since the interest earned during the sixth and seventh years combined is Rs. 292, we can calculate the interest earned during each year by dividing Rs. 292 by 2 (as it is divided over two years).

Interest earned per year = 292 / 2 = Rs. 146

Since the interest is earned at a simple interest rate, we can calculate the total interest earned over seven years by multiplying the interest earned per year by the number of years.

Total interest earned over seven years = 146 * 7 = Rs. 1,022

Next, we can calculate the maturity amount by adding the principal amount to the total interest earned.

Maturity amount = Principal amount + Total interest earned
Maturity amount = P + 1,022

Given that the maturity amount is Rs. 3,942, we can set up an equation:

3,942 = P + 1,022

Now we can solve the equation to find the principal amount (P).

P = 3,942 - 1,022
P = Rs. 2,920

Finally, we can calculate the rate percentage by dividing the interest earned over seven years (Rs. 1,022) by the principal amount (Rs. 2,920) and multiplying by 100.

Rate percentage = (Interest earned / Principal amount) * 100
Rate percentage = (1,022 / 2,920) * 100

Calculating this will give us the rate percentage.

Rate percentage = 34.932%

Rounding it to the nearest integer, we get approximately 34.93%. Therefore, the correct option is not listed.

Answer: None of the given options.

This is just a problem involving geometric series. So use your usual formulas.

p(1+r)^7 = 3942
p((1+r)^6 - 1) + p((1+r)^7) - 1) = 292
Now just solve for r as usual