Determine the area under the standard normal curve that lies

Determine the area under the standard normal curve that lies to the left of (a) Z= -0.55, (b) Z=1.15, (c) Z=0.21, (d) Z= -1.42

Solution

(a) Z= -0.55

P(Z<-0.55)=0.2912 (from standard normal table)

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(b) Z=1.15

P(Z<1.15) = 0.8749 (from standard normal table)

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(c) Z=0.21

P(Z<0.21) = 0.5832 (from standard normal table)

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(d) Z= -1.42

P(Z<-1.42) = 0.0778 (from standard normal table)