A sum when reckoned at 15% perannum amounts to 3920 ruppes in 3 years . Find the sum
To find the sum, we can use the formula for compound interest. The formula is:
A = P * (1 + r/n)^(n*t)
where:
A = the final amount (3920 ruppes in this case)
P = the principal amount (the sum we're trying to find)
r = the annual interest rate (15% in this case)
n = the number of times interest is compounded per year
t = the number of years (3 years in this case)
Let's plug in the values and solve for P.
3920 = P * (1 + 0.15/n)^(n*3)
We don't know the compounding frequency, so let's assume it's compounded annually (n = 1).
3920 = P * (1 + 0.15/1)^(1*3)
3920 = P * (1 + 0.15)^3
Now, we can simplify further.
3920 = P * (1.15)^3
3920 = P * 1.52
To isolate P, divide both sides of the equation by 1.52.
P = 3920 / 1.52
P = 2578.95
Therefore, the sum is approximately 2578.95 ruppes.