Do you know the answer to this?
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Answer:
The new 12 PM temperature should be 2.5 degrees Fahrenheit. And Dana is correct; you can subtract 1.4 from 2.5 (2.5 - ( -1.4) to find out the change in temperature from 6 AM to 12 PM on the second day.
Note:
Because of the direction the subtraction problem is set up between 2.5 and -1.4, the two negative signs will result in an addition sign according to the rules of algebra. Meaning that, the difference between -1.4 and 2.5 is approximately 3.9.