Answer:
0.87
Explanation:
The average daily change is the sum of daily changes divided by the number of days:
(3.24 -3/8 -0.15 +7/9)/4
= (3.492777...(repeating 7))/4
= 0.87319444...(repeating 4)
Rounded to hundredths, this is ...
0.87 °C average daily change
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Any calculator will compute the value of the expression we started with.