On a given morning the temperature was 81 degrees Fahrenheit. The temperature dropped 9 degrees Fahrenheit and then rose 5 degrees Fahrenheit. How much does the temperature need to rise or fall to return to the initial temperature of 81 degrees Fahrenheit?
Rise 4 degrees
Rise 9 degrees
Fall 4 degrees
Fall 5 degrees
To return to the initial temperature of 81 degrees Fahrenheit, the temperature needs to fall 4 degrees.
To find out how much the temperature needs to rise or fall to return to the initial temperature of 81 degrees Fahrenheit, we need to consider the changes that have already occurred.
First, the temperature dropped 9 degrees Fahrenheit. So the temperature after this drop is 81 - 9 = 72 degrees Fahrenheit.
Then, the temperature rose 5 degrees Fahrenheit. So the temperature after this rise is 72 + 5 = 77 degrees Fahrenheit.
To return to the initial temperature of 81 degrees Fahrenheit, the temperature needs to rise by 81 - 77 = 4 degrees Fahrenheit.
Therefore, the correct answer is to Rise 4 degrees Fahrenheit.