Physics
Grade-9
Easy
Question
An oven consumes 525 kWh of energy to provide 386 kWh of useful energy. What is its percentage efficiency?
- 73
- 73.5
- 74
- 90.5
Hint:
- Efficiency (%) = (useful energy output ÷ energy input) × 100
The correct answer is: 73.5
- Efficiency (%) = (useful energy output ÷ energy input) × 100
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