Conductive Heat Loss: Lower by 4.55% at 70F to 68F

[TPU]

Homework Statement

If only conductive heat loss was significant for a house, then by what percentage would you lower the heat loss if the temperature was reduced inside from 70°F to 68°F, when the outside temperature is 26°F? (Hint: Try using a ratio.)

Homework Equations

N/A, use a ratio

The Attempt at a Solution

This question was given with no explanation and no examples are present anywhere. I don't know what kind of equation to use since no area or R values are given. I did 70-26 and 68-26 then found the percentage between them which came out to 4.55%. Is this correct?

 

[haruspex]

I did 70-26 and 68-26 then found the percentage between them which came out to 4.55%. Is this correct?

Yes.
The conduction of heat through a wall is proportional to the temperature difference across it (70-26 versus 68-26).