Question

An Energy Star air conditioner unit costs $300 while a standard unit costs $200. The two units have the same cooling capacity. The Energy Star unit costs 5 cents per hour less to run. If you buy the Energy Star unit and run it for 12 hours per day for 6 months of the year, how long does it take to recover the $100 extra cost

Answer 1

Answer: 167 days

Explanation:

Energy star unit saves 5 cents per hour.

When run for 12 hours per day it saves:

= 5 * 12

= 60 cents

The extra cost of $100 in cents is:

= 100 * 100

= 10,000 cents

Days it will take for $100 to be recovered:

= 10,000 / 60

= 166.67 days

= 167 days

In 6 months you would have saved:

= 60 cents * 180 days

= 10,800 cents

= $108