It is known that the highest weekly average price for gasoline in California during 2005 was $3.15 per gallon and the lowest weekly average price for gasoline in California during 2005 was $2.56. Use this information to estimate the standard deviation of the weekly average price for gasoline in California during 2005. The standard deviation is ($3.15-2.56) / 6. I was wondering why you divide by 6?

Respuesta :

Answer:

$0.15

Step-by-step explanation:

To solve this problem, we apply the Range rule for estimating Standard deviation.

By the Range Rule:

Standard Deviation

Highest weekly average price for gasoline= $3.15 per gallon.

Lowest weekly average price for gasoline =$2.56 per gallon.

Therefore:

[tex]\text{Standard Deviation}\approx \dfrac{3.15-2.56}{4} \\=\dfrac{0.59}{4} \\\\=\$0.15 $(correct to the nearest cent).[/tex]

The standard deviation of the weekly average price for gasoline is approximately $0.15.

NOTE: You divide by 4 not 6.

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