Question

How do you do this on a ti-84 calculator?

Assume adult females have pulse rates that are normally distributed with a mean of 74.0 beats per minute and a standard deviation of 12.5 beats per minute. If 16 adult females are randomly selected, find the probability that they have pulse rates with a mean between 78 beats per minute and 90 beats per minute.

Answer 1

Given that, mean (μ) = 74.0 beats per minute and

standard deviation = 12.5 beats per minute

Sample size (n) = 16

The mean and standard deviation of the sampling distribution of the sample means are,

We want to find,

Using TI-83 plus calculator we find the above probabilitiy as follows :

Step 1) Press "2nd" key then press "VARS" key and go to the option "normalcdf".

Step 2) Enter the values as follows and press Enter you will get the required probability.

normalcdf (78, 90, 74.0, 3.125)

0.1003

Therefore, the probability that they have pulse rates with a mean between 78 beats per minute and 90 beats per minute is 0.1003

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