Physics
Grade-9
Easy
Question
An oven consumes 425 kWh of energy in order to provide 386 kWh of useful energy. What is its percent efficiency?
- 90%
- 91%
- 92%
- 93%
Hint:
- Efficiency (%) = (useful energy output ÷ energy input) × 100
The correct answer is: 91%
- Efficiency (%) = (useful energy output ÷ energy input) × 100
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