Assuming a Normal model applies,a town's average annual snowfall (in cm) is modeled by N ( 42 , 8 ) \mathrm { N } ( 42,8 ) N ( 42 , 8 ) Draw and label the Normal model.Then find the interval for the middle 95% of snowfall.A) ; 18 to 50 cmB) ; 34 to 50 cmC) ; 26 to 58 cmD) ; 34 to 66 cmE) ; 18 to 66 cm

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Assuming a Normal model applies,a town's average annual snowfall (in cm) is modeled by   N ( 42 , 8 )  \mathrm { N } ( 42,8 )  N ( 42 , 8 )    Draw and label the Normal model.Then find the interval for the middle 95% of snowfall.A)    ; 18 to 50 cmB)    ; 34 to 50 cmC)    ; 26 to 58 cmD)    ; 34 to 66 cmE)    ; 18 to 66 cm

Emely Kahrs · Accepted Answer

Final Answer : C, Explanation :  The Normal model is centered at the mean of the snowfall, which is 42 cm. The standard deviation is given as 10 cm.To find the interval for the middle 95% of snowfall, we need to find the z-scores that correspond to the lower and upper tails of 2.5% each. Using a standard Normal table or calculator, we find that the z-score for the lower tail is -1.96 and the z-score for the upper tail is 1.96.The interval for the middle 95% of snowfall is then given by:Mean ± z*(standard deviation)= 42 ± 1.96*(10)= 42 ± 19.6= (22.4, 61.6)Thus, the best choice is (C) 26 to 58 cm, which is the closest interval to (22.4, 61.6) and contains the mean.

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Assuming a Normal model applies,a town's average annual snowfall (in cm) is modeled by N(42,8) \mathrm { N } ( 42,8 ) N(42,8) Draw and label the Normal model.Then find the interval for the middle 95% of snowfall.A) ; 18 to 50 cmB) ; 34 to 50 cmC) ; 26 to 58 cmD) ; 34 to 66 cmE) ; 18 to 66 cm

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