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What percentage of the data in a standard normal distribution lies between x = .09 and x = 1.2?

User Wblaschko
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5 votes

Answer:

The percentage is
P(0.09 < \mu < 1.2 ) = 34.9\%

Explanation:

From the question we are told that

The random number is
x_1 = 0.09 \ and \ x_2 = 1.2

Generally the mean of standard normal distribution is
\mu = 0

The standard deviation of a standard normal distribution is
\sigma = 1

The percentage of the data in a standard normal distribution lies between


x_1 = 0.09 \ and \ x_2 = 1.2 is mathematically represented as


P(x_1 < \mu < x_2 ) = P((x_1 - \mu)/(\sigma ) <(X - \mu)/(\sigma ) < (x_2 - \mu)/(\sigma ) )


P(0.09 < \mu < 1.2 ) = P((0.09 - 0)/(1 ) <(X - \mu)/(\sigma ) < (1.2 - 0)/(1 ) )


P(0.09 < \mu < 1.2 ) = P(0.09 <(X - \mu)/(\sigma ) < 1.2 )

The
(X - \mu)/(\sigma ) = Z(The \ standardized \ value \ of \ X )


P(0.09 < \mu < 1.2 ) = P(0.09 <Z < 1.2 )


P(0.09 < \mu < 1.2 ) = P (Z < 1.2 )- P( Z<0.09)

From the z-table


P (Z < 1.2 )= 0.88493


P( Z<0.09) = 0.53586

So


P(0.09 < \mu < 1.2 ) = 0.88493 - 0.53586


P(0.09 < \mu < 1.2 ) = 0.349

Hence the percentage is


P(0.09 < \mu < 1.2 ) = 34.9\%

User Urbushey
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