Mineral Economics, Mine Planning, Systems Engineering · Mineral Economics · 2 marks · Numerical answer
In the economic block model, centre labels give extraction year and corner labels give block economic values in lakh rupees. At10% annual discount, find NPV in lakh to two decimals.
Collect values by year: year1 has+1+1=2 lakh; year2 has−1−1+2=0; year3 has−1−1+1=−1; year4 has+2. Discount to the present: NPV=2/1.1−1/1.1³+2/1.1⁴=2.4329 lakh, or2.43. Centre labels are years, not cash-flow amounts.
