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Repeatability assumption, select best of three projects

Short answer

Project A selected with lowest equivalent annual cost Rs 56,444/year at 14% MARR using repeatability assumption. AW calculated for each project's life cycle: A (3 yr), B (5 yr), C (7 yr). All have only costs, so minimum AW wins.

Use repeatability assumption to select the best project from the following three projects.

ProjectABC
Initial Investment100000200000250000
Annual Expenditure250002000015000
Useful Life, years357
Salvage Value400005000060000
MARR14%14%14%

Repeatability assumption: each project is repeated, with the same cash flows, as many times as needed, so all projects can be compared over a common (very long) period. Equal annual worth (AW) over one life cycle then represents every cycle, and lives need not be equal. All three projects have only costs, so the best is the one with the smallest annual cost (largest, i.e. least negative, AW).

AW = -I(A/P, i, N) - annual expenditure + S(A/F, i, N), MARR = 14%.

Project A (N = 3): (A/P,14%,3) = 0.4307, (A/F,14%,3) = 0.2907 AW = -100,000(0.4307) - 25,000 + 40,000(0.2907) = -43,073 - 25,000 + 11,629 = -56,444

Project B (N = 5): (A/P,14%,5) = 0.2913, (A/F,14%,5) = 0.1513 AW = -200,000(0.2913) - 20,000 + 50,000(0.1513) = -58,257 - 20,000 + 7,564 = -70,693

Project C (N = 7): (A/P,14%,7) = 0.2332, (A/F,14%,7) = 0.0932 AW = -250,000(0.2332) - 15,000 + 60,000(0.0932) = -58,298 - 15,000 + 5,592 = -67,707

ProjectLifeAW (Rs./year)
A3-56,444
B5-70,693
C7-67,707

Answer: Select Project A, the one with the lowest equivalent annual cost (Rs. 56,444 per year). B and C are costlier by about Rs. 14,249 and Rs. 11,263 per year respectively. (No revenue is given, so the projects are compared on cost alone, assuming they give equal service.)

✓ Answer checked by Claude Opus 5.5 (high effort)

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