MATH103 April 2009
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Question 07 (c)
Streptococcus viridans bacteria divide along a preferred axis and therefore form chains when they divide. You study a population of S. viridans in a blood culture. Let X be the length (in µm) of a randomly chosen chain. Its distribution is described by the probability density function
Find the standard deviation of X.
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If you are stuck, check the hint below. Consider it for a while. Does it give you a new idea on how to approach the problem? If so, try it!
Use the formula for the standard derivation
Recall from (a) that
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At first we calculate the Variance .
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MER QGH flag, MER QGQ flag, MER QGS flag, MER RT flag, MER Tag Variance and standard deviation, Pages using DynamicPageList parser function, Pages using DynamicPageList parser tag