1.Why in the solution of this question the last payment decommissioning expense of 6000/- is not included while calculating Discounted payback period ? 2.Monthly Interest is calculated using 1000(1.06^(1/12)-1)=4.8675 which is correct but cant we first take annual interest to be 6% of 1000 and then calculate monthly payment(say x) using 60= 12*x*(1-(1.0048675^(-12))/(.0048675)...where .004875 is effective monthly interest of 6% pa. Thanks already.
