GATE 2024 Chemical Engineering, Q35 · Plant Economics
The correct answer is 57.5 to 57.7.
Question
The capital cost of a distillation column is Rs. 90 lakhs. The cost is to be fully depreciated (salvage value is zero) using the double-declining balance method over 10 years. At the end of two years of continuous operation, the book-value of the column, in lakhs of rupees, rounded off to 1 decimal place, is _______
Official answer: 57.5 to 57.7
Why
GATE 2024 official key: 57.5 to 57.7. DDB rate = 2/n = 2/10 = 20%/yr. 72; lakhs.
Explanation cross-checked for consistency. Final answer matches the official IIT answer key.