Batter up! In baseball, a player’s batting average is the proportion of times the player gets a hit out of his total number of times at-bat. The distribution of batting averages in a recent season for Major League Baseball players with at least 100 plate appearances can be modeled by a Normal distribution with mean μ=0.261 and standard deviation σ=0.034Sketch the Normal density curve. Label the mean and the points that are 1,2, and 3 standard deviations from the mean.

Short Answer

Expert verified

Mean,μ=0.261

Standard deviation,σ=0.034

Step by step solution

01

Given information

Mean,μ=0.261

Standard deviation,σ=0.034

02

Calculation

In a normal distribution, 68percent of the data lies within 1 standard deviation of the mean.

In a normal distribution, 95%of the data lies within 2standard deviations of the mean.

A normal distribution has 99.7%of its data inside 1 standard deviation of the mean.

Then

The general Normal density graph is represented as:

Now,

On both sides of the mean, find the standard values.

From left to the mean,

3standard deviation:

μ3σ=0.2613(0.034)=0.159

2standard deviation:

μ2σ=0.2612(0.034)=0.193

1standard deviation:

μσ=0.2610.034=0.227

From right to the mean,

1standard deviation:

μ+σ=0.261+0.034=0.295

2standard deviations:

μ+2σ=0.261+2(0.034)=0.329

3standard deviation:

μ+3σ=0.261+3(0.034)=0.363

To show the Normal density curve, write the estimated values in the figure below:

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