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The amount of snowfall falling in a certain mountain range is normally distributed with a mean of 105 ' and a standard deviation of 10 ' what is the probability that the mean annual snowfall during 25 randomly picked years will exceed 107.8 'your answer should be a decimal rounded to the fourth decimal place.

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The sample mean is μ=105, and sample standard deviation is σₓ=
(σ)/(√(n)) =(10)/(√(25)) =2.

The Z-score is
Z=( 107.8-105)/(2)=1.4.

Refer to standard normal distribution table.

The required probability is


P(X>107.8)=P(Z>1.4)=1-P(Z<1.4)=0.0808

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