A = Rs 170 future value

t = 2 years

r = 12.5% annual interest rate

m = 1 number of compounding period per year

n = 2 the number of compounding periods

i = r/m = 12.5% interest per period

P = ? the principal

A = P(1 + i)^n

P = A/(1 + i)^n

P = 170/(1 + 0.125)^2

P = 170/1.265625

P = Rs 134.321

the sum that yield an amount of rs.170 after 2 years at 12.5% p.a. interest being compounded annually is Rs 134.321.