Question

A light bulb consumers 1800 watt-hours per day. How long does it take to consume 9450 watt-hours?

Answer 1

9900 watts-hours is how much it consumes in a period of 5 days and 12 hours.............

to check this: multiply 1800 by 5 and it equals 9000 then you divide 1800 by 2 because 12hours is a half day and it is 900 after all that you add 9000+900 and it equals 9900.