Engineering Board Exam Reviewer · Energy and Power · medium
A 40 W lamp is on for 5 hours each day. At P12 per kWh, how much does it cost for a 30-day month?
- P7.20
- P720
- P36
- P72
Answer
D. P72
Solution
Energy =0.04 kW×5 h×30=6 kWh. Cost =6×12=P72.
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