An expansion of the current BIM (Building Infor­mation Model) software has been proposed to First Financial, the building’s owner. A total installed cost of $120,000 is expected to generate additional savings of $40,000 per year for 10 years, after which time the software will be replaced with no salvage value. The annual M&O cost is expected to be $10,000 the first year and increase by an arithmetic gradient G between $1000 and $5000 per year thereafter. Determine if the ex­panded BIM is sensitive to gradient increases of $1000 (optimistic), $3000 (most likely), and $5000 (pessimistic) per year. Use AW analysis and a MARR of 10% per year.

What will be an ideal response?


AWOpt = -120,000(A/P,10%,10) - [10,000 + 1000(A/G,10%,10)] + 40,000
= -120,000(0.16275) - [10,000 + 1000(3.7255)] + 40,000
= $6745

AWML = -120,000(A/P,10%,10) - [10,000 + 3000(A/G,10%,10)] + 40,000
= -120,000(0.16275) - [10,000 + 3000(3.7255)] + 40,000
= $-706.50

AWPess = -120,000(A/P,10%,10) - [10,000 + 5000(A/G,10%,10)] + 40,000
= -120,000(0.16275) - [10,000 + 5000(3.7255)] + 40,000
= $-8158

The decision to expand the BIM is sensitive to gradient increases.

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