Question

In: Statistics and Probability

4. a. Suppose Z~Normal(0,1). Find P(1<Z<2). (3pts) b. Suppose X~Normal(-2,1). Find P(X>0 or X<-3). (3pts) c....

4.

a. Suppose Z~Normal(0,1). Find P(1<Z<2). (3pts)

b. Suppose X~Normal(-2,1). Find P(X>0 or X<-3). (3pts)

c. Suppose X~Normal(2,4). The middle 88% of the X values are between what two values? (3pts)

Expert Solution

Refer Standard normal table/Z-table to find the probability or use excel formula "=NORM.S.DIST(2, TRUE)" & "=NORM.S.DIST(1, TRUE)" to find the probability.

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Refer Standard normal table/Z-table to find the probability or use excel formula "=NORM.S.DIST(2, TRUE)" & "=NORM.S.DIST(-1, TRUE)" to find the probability.

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Refer Standard normal table/Z-table, Lookup for z-score corresponding to area 0.94 to the left of the normal curve or use excel formula "=NORM.S.INV(0.94)" to find the z-score.

orchestra answered 2 years ago

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