Question

Preston's clock produces 45 useful energy units for every 100 units of electricity used. What is the efficiency of the clock?

Answer 1

Answer:

9 : 20

Explanation:

If 1 useful energy unit = 1 unit of electricity

then a ratio of efficiency would form

= 45 : 100 (This can be simplified further)

= 9 : 20 (When divided by 5)

Therefore answer = 9 : 20

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