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Question
Choose the correct option from the given alternatives:
A die is thrown 100 times. If getting an even number is considered a success, then the standard deviation of the number of successes is ______.
Options
`sqrt50`
5
25
10
Solution
A die is thrown 100 times. If getting an even number is considered a success, then the standard deviation of the number of successes is 5.
Explanation:
n = 100
p(getting even number) = `3/6 = 1/2`
q(not even number) = `3/6 = 1/2`
SD = `sqrt(variance(x)) = sqrt(npq)`
= `sqrt(100 xx 1/2 xx 1/2)`
= `sqrt25`
= 5
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Solution:
A pair of dice is thrown 3 times.
∴ n = 3
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