Problem

Give your answers to four decimal places (for example, 0.1234).
(a) Find the area under the standard normal curve to the right of $z=-1.06$.
(b) Find the area under the standard normal curve between $z=1.28$ and $z=2.74$.

Answer

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Answer

Final Answer: \n(a) The area under the standard normal curve to the right of \(z=-1.06\) is approximately \(\boxed{0.8554}\).\n(b) The area under the standard normal curve between \(z=1.28\) and \(z=2.74\) is approximately \(\boxed{0.0972}\).

Steps

Step 1 :The standard normal curve is a special case of the normal distribution where the mean is 0 and the standard deviation is 1. The area under the curve represents the probability of a random variable falling within a certain range.

Step 2 :To find the area under the standard normal curve to the right of \(z=-1.06\), we need to calculate the cumulative distribution function (CDF) at \(z=-1.06\) and subtract it from 1. This is because the total area under the curve is 1, and the CDF gives the area to the left of a given \(z\)-score.

Step 3 :After calculation, the area under the standard normal curve to the right of \(z=-1.06\) is approximately 0.8554277003360904.

Step 4 :To find the area under the standard normal curve between \(z=1.28\) and \(z=2.74\), we need to calculate the CDF at \(z=1.28\) and \(z=2.74\) and subtract the former from the latter.

Step 5 :After calculation, the area under the standard normal curve between \(z=1.28\) and \(z=2.74\) is approximately 0.09720060873579162.

Step 6 :Final Answer: \n(a) The area under the standard normal curve to the right of \(z=-1.06\) is approximately \(\boxed{0.8554}\).\n(b) The area under the standard normal curve between \(z=1.28\) and \(z=2.74\) is approximately \(\boxed{0.0972}\).

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