Electrical mathQuestion 1373 of 1506

A 4.5 kW heater runs 5 hours each day for 5 days. Energy costs 8 cents per kWh. What is the total cost?

  1. $9.00
  2. $90.00
  3. $1.80
  4. $13.50
Show answer

Correct answer: $9.00

Energy = 4.5 × 5 × 5 = 112.5 kWh. Cost = 112.5 kWh × $0.08 = $9.00.

Source: Computed, 12.3: Power Measurement

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Questions last reviewed: 18 October 2026