ELECTRIC BILL

Many village people pay their electric bill not knowing which household items use the most electricity. The following problems will help clarify where the money goes.

 Multiply Divide Percentage Ratio proportion Multi step problems

COFFEE POT

A coffee pot uses 1600 watts per hour.

The cost of electricity in the village is \$.55 a KWH (kilowatt hour, which is 1000 watts for one hour.)

How much does it cost to run the coffeepot for each hour? ______________

State energy assistance reduces the cost per KWH by 45%. How much does it cost the owner to run the coffeepot per hour? _______________

LIGHT BULB

A 75 watt bulb costs how much to run for a 6 hour evening with village electricity at \$.45/kwh.

How much is a 60 watt bulb for the same location and time? _________________

CIRCULAR SAW

A circular saw draws 10 amps at 120 volts. Amps x volts =Watts

At \$.55/KWH, how much does it cost to run a circular saw for 30 minutes? ________________

A worm drive saw uses 12 amps. How many kilowatts does it use in 30 minutes? ____________

 10 amps 12 amps

MONITOR/TOYO STOVE

A Monotor stove uses 90 watts when it operates. It is on for 40% of the winter day. Electricity is \$.45/KWH.

What is the electrical cost of running a Monitor stove? _______________

If fuel is \$3.00 a gallon, and the stove uses 3 gallons on a winter day, what is the total cost of operation? ___________________

WELDER (CHALLENGE)

Wayne bought a welder. It draws 40 amps at 240 volts.

Remember, Volts x Amps = Watts.

It is a 20% duty cycle welder, that is, it can be run only 20% of the time.

It must be cooled for 80% of the time.

What does it cost him to operate the welder for an hour if village electric-ity is \$.55/KWH? (20% on & 80% cooling)

MICROWAVE

A microwave uses quite a bit of electricity, but for very short periods of time. Popcorn takes an average of 3 minutes to pop. With the microwave drawing 1600 watts, and village electricity costing \$.50/kwh, how much does it cost to pop popcorn?

TV & VCR

A TV uses 60 watts. A VCR uses 20 watts.

How much does the electricity cost to run both of them for a 2 hour movie in a village where electricity is \$.57/kwh?