The National Sporting Goods Association (NSGA) conducted a survey of the ages of individuals that purchased skateboarding footwear. The ages of this survey are summarized in the following relative frequency distribution. Suppose the survey was based on a sample of 200 individuals. Age of User Percent Under 14 years old 35 14 to 17 years old 41 18 to 24 years old 15 25 to 34 years old 4 35 to 44 years old 4 45 to 64 years old 1 Calculate the mean, variance and standard deviation of the age of individuals that purchased skateboarding shoes. Use 10 as the midpoint of the first class. (Round your answers to 2 decimal places.)

μ = 16.31

σ² = 11.22

σ = 3.35

Step-by-step explanation:

The mean is the sum of the midpoints times the percentage.

μ = ∑ (mx)

The variance is the sum of the squared differences between the midpoints and the mean, all divided by the total number of people minus one.

σ² = ∑ (m − μ)² / (n − 1)

And the standard deviation is the square root of the variance.

First, we calculate the mean.

Now, we find the variance.

The standard deviation is therefore σ = 3.35.

sine

step-by-step explanation:

i believe the correct answer is option 4.principalities were small territories that were run by russian rulers.

which statement correctly defines principalities in northern asia in the 1200s? principalities were small territories that were run by russian rulers.

hope i could ! : )