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Question

Given a standardized normal distribution (with a mean of 0 and a standard devication of 1,) determine the following probabilities.

Solution

a)

Using a table/technology, the right tailed area of this is          
          
P(z >   1.04   ) =    0.14916995 [answer]

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b)

Using a table/technology, the left tailed area of this is          
          
P(z <   -0.28   ) =    0.389738752 [answer]

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c)

Do you mean -1.96<z<-0.28? It has to be, becasue 1.96 is greater than 0.28, so it wouldn\'t make sense. I assumed there\'s a negative sign there.

z1 = lower z score =    -1.96      
z2 = upper z score =     -0.28      
          
Using table/technology, the left tailed areas between these z scores is          
          
P(z < z1) =    0.024997895      
P(z < z2) =    0.389738752      
          
Thus, the area between them, by subtracting these areas, is          
          
P(z1 < z < z2) =    0.364740857   [ANSWER]