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AP®︎/College Statistics

Course: AP®︎/College Statistics > Unit 8

Lesson 2: Mean and standard deviation of random variables

Mean (expected value) of a discrete random variable
Mean (expected value) of a discrete random variable
Interpreting expected value
Interpret expected value
Variance and standard deviation of a discrete random variable
Standard deviation of a discrete random variable
Mean and standard deviation of a discrete random variable

Standard deviation of a discrete random variable

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Anasia is a basketball player who regularly shoots sets of

2

free-throws. Suppose that each shot has probability

0.7

of being made, and the results of the shots are independent.

The table below displays the probability distribution of

X

, the number of shots that Anasia makes in a set of

2

attempts.

$X = # of makes$ ‍	$0$ ‍	$1$ ‍	$2$ ‍
$P (X)$ ‍	$0.09$ ‍	$0.42$ ‍	$0.49$ ‍

Given that $μ_{X} = 1.4$ ‍ makes, find the standard deviation of the number of shots that Anasia makes.
Round your answer to two decimal places.

σ_{X} \approx

shots

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AP®︎/College Statistics

Course: AP®︎/College Statistics > Unit 8

Problem