An energy client wants a rough figure before commissioning a study. India's population is about 140 crore across roughly 6.5 lakh villages and around 4,500 towns and cities.
Estimate the number of petrol pumps in India. Build it from vehicle demand or from geographic coverage, say which you chose and why, and sanity-check the result.
100 points, 60% to pass.
Two routes. Demand-side: vehicles on the road × litres per vehicle per year ÷ throughput per pump per year. Supply-side: settlements × pumps per settlement, weighted by size. The demand route is more defensible because throughput per pump is a figure a candidate can reason about (a pump that sells less than a few thousand litres a day does not survive). A good answer picks one, mentions the other as a cross-check, and notes that rural coverage is driven by policy obligation rather than economics.