Use the Normal Distribution table to find the proportion of

Use the Normal Distribution table to find the proportion of the normal curve that is

At or above a z-score of 1.25

At or below a z-score of -1.00

Between the z-scores of 1.50 and .25

Between the z-scores of 1.00 and .50

Solution

a)

To get the area above a z score, we

1. Get the left tailed area using a table.
2. Subtract the area from 1.

Thus,

P(z>1.25) = 1 - P(z<1.25) = 0.8944 = 0.1056 [ANSWER]

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b)

The table readily gives this to you,

P(z<-1.00) = 0.1587 [ANSWER]

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c)

We subtract the left tailed area of these two z scores to have

P(0.25<z<1.50) = 0.5987 - 0.9332 = 0.3345 [answer]

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d)

The same way as C,

P(0.50<z<1) = 0.8413 - 0.6915 = 0.1498 [ANSWER]