Answer:
Analysis of Total cost over the period of 7 years
Retain Old Buy New Total
1.Variable Operating Cost $640,100 $581,800 ($58,300)
2.Old Machine Book Value
Retain; Annual Depreciation $12,971 $0 ( $12,971)
Replace: Lump sum Written Off $0 $90,800 $90,800
3.Old Machine Disposal Value $0 ($27,200) ($27,200)
4.Initial Purchase Cost New $0 $407,400 $407,400
Total Cost $653,071 $1052,800 $399,729
Explanation:
Replacement of Machine is a Capital Investment or Long term decision.One aspect of asset replacement is how to deal with book value (written down value) of old equipment.