1. EXAMPLE 3
Find the mean
TEMPERATURE
The table gives the daily minimum temperatures (in degrees Fahrenheit) in Barrow, Alaska, for the first 5 days of February Find the mean daily minimum temperature.

2. EXAMPLE 3
Find the mean
SOLUTION
To find the mean daily minimum temperature, find the sum of the minimum temperatures for the 5 days and then divide the sum by 5. =
–21 + (–29) + (–39) + (–39) + (–22) 5
Mean
150 5 – = = – 30
The mean daily minimum temperature
was –30°F.
ANSWER

3. Simplify an expression
EXAMPLE 4
Simplify an expression
Simplify the expression
36x 24 6 – .
36x 24 6 – =
36x 24 – 6 ( )
Rewrite fraction as division. =
36x 24 – 1 6 ) (
Division rule =
36x 1 6 – 24
Distributive property
6x – 4 =
Simplify.

4. 9. Find the mean of the numbers –3, 4, 2.8, and –1.5 .
GUIDED PRACTICE
for Examples 3 and 4
9. Find the mean of the numbers –3, 4, 2.8, and –1.5 .
The mean is
ANSWER
Temperature
Find the mean daily maximum temperature (in degrees Fahrenheit) in Barrow, Alaska, for the first 5 days of February 2004.
Day in February 1 2 3 4 5
Minimum temperature (°F)
– 3
– 20
– 21
– 22
– 18

5. GUIDED PRACTICE
for Examples 3 and 4
The mean daily minimum temperature was –16.8°F.
ANSWER

6. GUIDED PRACTICE
for Examples 3 and 4
Simplify the expression
2x – 8 –4
11.
– x = 1 2
+ 2
–6y +18 3
12.
= –2y + 6
–10z – 20 –5
13.
= 2z + 4