The average change is 3 degrees per hour.
To calculate the average of any data we have to divide the change by the time taken for that change.
let us suppose there is a data 4,5,6,7 and 8.
Average of the data will be the sum of data divided by the number of terms.
Average=
=
= 6
So now we will calculate the average change in temperature per hour,
Given that there is a fall of 12 degrees in 4 hours.
Average change per hour=
= 3 degrees per hour
So, the required change is 3 degrees per hour.
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