# Problem of the Week Problem A and Solution Power Savings

## Problem

An electric clothes dryer uses approximately $$5$$ kilowatt-hours of energy to dry a single load of laundry.

On average, Mary Lois’s family washes $$4$$ loads of laundry per week. If they use a clothes line instead of the electric dryer to dry half of their loads of laundry, approximately how many kilowatt-hours of energy will they save in a year?

## Solution

Since half of $$4$$ is $$2$$, then on average Mary Lois’s family uses the clothes line to dry two loads of laundry per week. This means they would save approximately $$2 \times 5 = 10$$ kilowatt-hours of energy each week. Since there are approximately $$52$$ weeks in a year, we calculate the total savings as $$52 \times 10 = 520$$ kilowatt-hours of energy.