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Repeatability, 4-year study, infinite life

Short answer

Repeatability: AW A = Rs10,268, AW B = Rs11,349; select B. For4-year study with B's salvage Rs2,50,000, AW B = -309; select A. Infinite life: capitalized worth A = Rs85,566, B = Rs94,571; select B.

Select the best project.

Project AProject B
Initial investment (Rs.)3,50,0005,00,000
Annual revenues (Rs.)1,90,0002,50,000
Annual expenses (Rs.)64,5001,38,000
Useful life (years)48
Salvage value at the end of useful life00
Use
a) Repeatability assumption
b) Study period is 4 years
c) Infinite project life

Net annual revenue = revenue − expenses: A = 1,90,000 − 64,500 = 1,25,500; B = 2,50,000 − 1,38,000 = 1,12,000. Salvage values are zero. MARR is not given; assume 12%.

a) Repeatability assumption (compare AW over own lives)

AW(A) = −3,50,000(A/P,12%,4) + 1,25,500
      = −3,50,000(0.32923) + 1,25,500 = 10,268
AW(B) = −5,00,000(A/P,12%,8) + 1,12,000
      = −5,00,000(0.20130) + 1,12,000 = 11,349

B has the higher AW. Select B.

b) Study period = 4 years

Only the first 4 years of B are used, so B must be sold at year 4. Its value then is not given; assume it falls straight-line from 5,00,000 to 0 over 8 years, i.e. Rs 2,50,000 at year 4.

AW(A, 4 yr) = 10,268
AW(B, 4 yr) = −5,00,000(A/P,12%,4) + 2,50,000(A/F,12%,4) + 1,12,000
            = −164,617 + 52,309 + 1,12,000 = -309

With no resale value at all, AW(B) would be even lower (−52,617). Either way A is clearly better. Select A.

c) Infinite project life

Capitalized worth CW = AW / i (projects repeated for ever).

CW(A) = 10,268 / 0.12 = 85,566
CW(B) = 11,349 / 0.12 = 94,571

Select B.

BasisAW(A)AW(B)Choice
a) Repeatability10,26811,349B
b) 4-year study10,268-309A
c) Infinite (CW)85,56694,571B

Answer: B under repeatability and for infinite life; A when only 4 years of service are needed.

✓ Answer checked by Claude Opus 5.5 (high effort)

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