The estimated average energy that I used to operate a cloths dryer for a year is is kW•h. If the average rate to operate the dryer is 7.15 cents/kW•h, what is the average cost per year.

Insufficient data. How much time, on average, do you use it? This would depend on how often do you use it, and how much time do you set it for each time you use it.

To determine the average cost per year, you will need to multiply the estimated average energy consumption by the average rate.

Let's assume the estimated average energy consumption is x kW•h.

The average cost per year can be calculated as:

Average cost per year = Estimated average energy consumption (x kW•h) * Average rate (7.15 cents/kW•h)

Therefore, the average cost per year is x * 7.15 cents.