Problem

Assume that females have pulse rates that are normally distributed with a mean of $\mu=73.0$ beats per minute and a standard deviation of $\sigma=12.5$ beats per minute. Complete parts (a) through (c) below.
a. If 1 adult female is randomly selected, find the probability that her pulse rate is less than 76 beats per minute.
The probability is 0.5948 .
(Round to four decimal places as needed.)
b. If 25 adult females are randomly selected, find the probability that they have pulse rates with a mean less than 76 beats per minute.
The probability is
(Round to four decimal places as needed.)

Answer

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Answer

Final Answer: The probability that a randomly selected female has a pulse rate less than 76 beats per minute is approximately \(\boxed{0.5948}\).

Steps

Step 1 :We are given that the mean pulse rate of females is \(\mu = 73.0\) beats per minute and the standard deviation is \(\sigma = 12.5\) beats per minute.

Step 2 :We are asked to find the probability that a randomly selected female has a pulse rate less than 76 beats per minute.

Step 3 :This is a problem of normal distribution. We can use the z-score formula to find the z-score for 76, which is \(z = \frac{x - \mu}{\sigma}\), where \(x\) is the value we are interested in.

Step 4 :Substituting the given values into the formula, we get \(z = \frac{76 - 73}{12.5} = 0.24\).

Step 5 :We can then use a z-table to find the probability that a z-score is less than the calculated value. The probability is approximately 0.5948.

Step 6 :Final Answer: The probability that a randomly selected female has a pulse rate less than 76 beats per minute is approximately \(\boxed{0.5948}\).

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