How many kwh of electricity would have been consumed?

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During 4 hours one winter afternoon, when the outside temperature was 11° C, a house heated by electricity was kept at 23° C with the expenditure of 44 kwh (kilowatt·hours) of electric energy.
(a) What was the average energy leakage in joules per second (watts) through the walls of the house to the environment (the outside air and ground)?
11000 watts

(b) The rate at which energy is transferred between two systems due to a temperature difference is often proportional to their temperature difference. Assuming this to hold in this case, if the house temperature had been kept at 26° C (78.8° F), how many kwh of electricity would have been consumed?

i got a with power/deltat
but idk how to do be someone help
 
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Proportional means if the temperature difference was twice as much the power used would be twice as much
 
the difference is 3 degrees so it would be 3 times as much power?
 
i just tried 11kw/12degrees and got .916666 so i took that and multiplied it by 15 the other change in temp and got 13.75kwh this is wrong can someone help me?
 
Sorry for the delay - didn't see the reply.

The temperature difference you care about is between the inside and outside of the house, not the change from part a to part b, - the temperature doesn't have a memory of what the question was!

Initial temperature difference = 23-11, later temperature difference was 26-11
How much larger is the second? As a proprtion of the first?