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Repeatability, two mutually exclusive options

Short answer

Using repeatability and AW at 12% MARR: Option I AW = Rs. 628/yr, Option II AW = Rs. 690/yr. Both positive; Option II has higher annual worth. Recommend Option II.

Consider the following two mutually exclusive alternatives, recommend the best alternative using repeatability assumptions. MARR = 12%

Option-I (Rs.)Option-II (Rs.)
Initial Cost20,00030,000
Annual receipts10,00014,000
Annual cost5,0008,000
Salvage Value40000
Useful Life6 years10 years

Repeatability assumption: each option is repeated with identical cash flows, so the unequal lives (6 and 10 years) are compared by annual worth (AW) over one cycle of each. MARR = 12%.

Option I (N = 6)

(A/P, 12%, 6) = 0.2432, (A/F, 12%, 6) = 0.1232 AW = -20,000(0.2432) + (10,000 - 5,000) + 4,000(0.1232) = -4,865 + 5,000 + 493 = Rs. 628 per year

Option II (N = 10)

(A/P, 12%, 10) = 0.1770 AW = -30,000(0.1770) + (14,000 - 8,000) + 0 = -5,310 + 6,000 = Rs. 690 per year

OptionLifeAW (Rs./yr)
I6628
II10690

Both are positive (acceptable), and Option II has the larger AW.

Answer: Recommend Option II, which gives about Rs. 62 more annual worth than Option I.

✓ Answer checked by Claude Opus 5.5 (high effort)

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