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Step-5

Title: Measures of variation- Population Standard deviation

Grade: 9-a Lesson: S2-L2

Explanation: Hello Students, time to practice and review the steps for the problem.

Step	Type	Explanation	Answer
1	Problem	Find the standard deviation from the given data 2.5,9.2,1.6,3.7,1.1
2	Step	To find the mean \$\mu\$ = \$(2.5+9.2+1.6+3.7+1.1)/(5)\$ = \$18.1/5\$ = 3.62
3	Step	Subtracting each score from mean and square each deviation $1$
4	Step	Add the squared deviation \${X_i - \mu}^2\$	1.25+31.13+4.1+0.0064+6.3 = 42.7
5	Step	Divide the sum by number of scores to get the variance	\$frac\{42.7}{5}\$ = 8.55
6	Step	Take the square root of the squared deviation (or) variance	\$\sqrt(8.55)\$ \$\approx\$ 2.9
7	Step	Population standard deviation	\$\sigma\$ = 2.9
8		Answer	C

Step

Type

Explanation

Answer

Problem

Find the standard deviation from the given data 2.5,9.2,1.6,3.7,1.1

Step

To find the mean \$\mu\$ = \$(2.5+9.2+1.6+3.7+1.1)/(5)\$ = \$18.1/5\$ = 3.62

Step

Subtracting each score from mean and square each deviation
$1$

Step

Add the squared deviation \${X_i - \mu}^2\$

1.25+31.13+4.1+0.0064+6.3 = 42.7

Step

Divide the sum by number of scores to get the variance

\$frac\{42.7}{5}\$ = 8.55

Step

Take the square root of the squared deviation (or) variance

\$\sqrt(8.55)\$ \$\approx\$ 2.9

Step

Population standard deviation

\$\sigma\$ = 2.9

Answer

Tutor: Questions

Seq	Type	Question
1	Problem	What did you learn from this problem?
2	Clue	What did you learn from the clues?
3	Hint	What did you learn from the Hints?
4	Step	What did you learn from the Steps?
5	Step	How can we improve the Steps?

Seq

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Clue

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Step

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