Let us consider an annuity whose periodic payment is Rs. R payable at the end of each payment period for 'n' periods, interest paid r% per period or \(\rm i=\frac{r}{100}\) so the amount of obligation can be given as _____.
1
\(\rm A=R\left[\frac{(1+i)^n-1}{i}\right]\)
2
\(\rm A=R\left[\frac{(1-i)^n-1}{i}\right]\)
3
\(\rm A=R\left[\frac{(1+i)^n}{i}-1\right]\)
4
A = R[in-1 - 1]