A half hour is 30 minutes. So you would need to divide 30 by 5 and you get six. Multiple 6 degrees Fahrenheit by 6 and you get 36 degrees. The solution cooled 36 degrees in half an hour.
Hope this helps!
METHOD 1
f(3) = 20
f(4) = 30
f(5) = 42
f(6) = 56
rate of change
f(4)-f(3)=10
f(5)-f(4)=12
f(6)-f(5)=14
then the average of change is 10+12+14 /3 = 12
METHOD 2 --- faster
rate of change = f(6)-f(3) / 6-3
= (36+18+2)-(9+9+2) / 3
= 36/3 = 12
Answer:
$
or ≈$
Step-by-step explanation
The question states that Mrs. Hadley spent $126.97 on one month, $237.81 on the next, and $198.42 on the last. To get the total, we can add these values together.

An estimation would be:

We can use this estimation to determine that the total value is reasonable.
Can you please answer my question