Using the mean concept, the expression that gives the average of the low and high temperatures is:
(-3 + 8)/2.
The mean of a data-set is given by the sum of all observations in the data-set divided by the number of observations.
In this problem, the two observations are -3 and 8, hence their average is given by:
(-3 + 8)/2.
More can be learned about the mean concept at https://brainly.com/question/25122507
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