An electric shower of 2,000 W is used 30 minutes a day for 30 days. The energy costs 0.80 reais per kWh. What is the monthly cost?
Answer and explanation
Correct answer: B. BRL 24.00
- Step 1: Energy per day = 2 kW x 0.5 h = 1 kWh; in 30 days = 30 kWh. Step 2. Cost = 30 x 0.80 = 24. Answer: BRL 24.00. Why not the others: The other results use the wrong time, days or power conversion.
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