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Both BCR with FW, gradient revenue

Short answer

Conventional B/C = 1.05; modified B/C = 1.07. Both exceed 1, so the project is marginally acceptable at 15% MARR.

Determine both types of B/C ratio by using FW formulation.

Initial investment (Rs.)2,50,000
Annual revenue (Rs.)50,000 at the end of first year and increasing by Rs. 30,000 for each year
Annual O&M cost (Rs.)30,000
Salvage value (Rs.)50,000
Useful life (year)5
MARR15%

Revenue is a gradient series: 50,000, 80,000, 1,10,000, 1,40,000, 1,70,000 (base 50,000, G = 30,000). O&M = 30,000 per year, salvage 50,000 at year 5, MARR = 15%.

 revenue: 50k  80k  110k  140k  170k      O&M: 30k each year
 year :    1    2    3     4     5        yr 5: +50k salvage;  yr 0: -2,50,000

Factors at 15%, 5 years: (F/A) = 6.7424, (F/P) = 2.0114, (A/G) = 1.7228

  • Equivalent uniform revenue = 50,000 + 30,000 (A/G, 15%, 5) = 50,000 + 30,000 × 1.7228 = 101,684
  • FW(B) = 101,684 × 6.7424 = Rs 685,595
  • FW(O&M) = 30,000 × 6.7424 = Rs 202,271
  • FW(I) = 2,50,000 × 2.0114 = Rs 502,839
  • S = Rs 50,000

Conventional B/C = FW(B) / [FW(I) + FW(O&M) − S] = 685,595 / (502,839 + 202,271 − 50,000) = 685,595 / 655,111 = 1.047

Modified B/C = [FW(B) − FW(O&M)] / [FW(I) − S] = (685,595 − 202,271) / (502,839 − 50,000) = 483,324 / 452,839 = 1.067

Answer: conventional B/C = 1.05, modified B/C = 1.07. Both are slightly greater than 1, so the project is marginally acceptable at MARR = 15%.

✓ Answer checked by Claude Opus 5.5 (high effort)

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