Answer: Old machine should be replaced.
Step-by-step explanation:
The variable manufacturing cost will reduce by:
= 624,000 - 524,000
= $100,000
Over a period of 5 years this will be:
= 100,000 * 5
= $500,000
Selling the old machine would bring in $32,000:
= 500,000 + 32,000
= $532,000
The cost of the new machine would reduce this gross benefit by:
= 532,000 - 455,100
= $76,900
Net income will increase by a total of $76,900 over the 5 year period if the new machine is bought so it should be bought.