You're looking for a value

such that

Because the distribution is symmetric, the value of

in either case will be the same.
Now, because the distribution is continuous, you have that

The mean for the standard normal distribution is

, and because the distribution is symmetric about its mean, it follows that

.

You can consult a

score table to find the corresponding score for this probability. It turns out to be

.
21.6 miles per gallon
Multiplied by 6.2 gallons
21.6 * 6.2 = 133.92
Cheryl can travel 133.92 (or about 134) miles on 6.2 gal. of gas.
Hope that helped!
Answer:
13.20 teaspoon of fertiliser needed for entire garden.
Step-by-step explanation:
Diameter of the garden = 14.50 ft
Radius of the garden = 7.25 ft
Area
[tex]A=\pi r^2[/text]
[tex]A=\pi \times 7.25 \times 7.25[/text]
[tex]\pi=3.14[/text]
[tex]A=\pi \times 7.25 \times 7.25[/text]
[tex]A=3.14 \times 7.25 \times 7.25[/text]
Hence
[tex]A=165.046[/text]
Area is 165.046 Sq Ft
For 25 sq ft of fields the fertiliser needed = 2 tea spoon
For 1 sq ft of fields the fertiliser needed =
[tex]\frac{2}{25}[/text] tea spoon
For 165.046 sq ft of fields the fertiliser needed =
[tex]\frac{2 \times 165.046 }{25}[/text] tea spoon
For 165.046 sq ft of fields the fertiliser needed = 13.20 tea spoon