A 3000 W heater is on for 3 hours. Electricity costs 30 cent per kWh. What is the cost?
Answer and explanation
Correct answer: A. 270 cent
- Step 1: Energy kWh.
- Step 2: Cost cent.
Answer
270 cent.
Why not the others: 270000 cent: the power is not converted to kW. 9 cent: that is the energy in kWh, not the cost. 33 cent: the numbers are added.
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