Question

Use technology to find the​ P-value for the hypothesis test described below.

The claim is that for the population of adult​ males, the mean platelet count is mu μ <202. The sample size is n=55 and the test statistic is t=−1.254.

How would I solve this using a TI-84? Please explain your steps. Thank you!

Answer 1

Solution :

The null and alternative hypotheses are as follows :

To test the hypothesis we shall use one sample t-test.

We are given that, value of the test statistic is t = -1.254.

Degrees of freedom (df) = (n - 1) = (55 - 1) = 54

Since, our test is left-tailed test therefore, we shall obtain left-tailed p-value for the test statistic. The left-tailed p-value is given as follows:

p- value = P(T < t)

p-value = P(T < -1.254)

To obtain the p-value we can use TI-84 calculator.

Press the key named as "2nd" in TI-84 and then press the key "VARS". After pressing these two keys you will get many functions. Select the function named as "tcdf". When you will select the function "tcdf" you will need to provide the values for three arguments to the function of "tcdf". The three arguments are as follows :

1) lower

2) upper

3) df

Enter the number 1000000 for lower, enter the number -1.254 for upper and enter the number 54 for df. After providing these values to the arguments, press enter key of your calculator two times you will get the left-tailed p-value for the test statistic.

When we follow the above given steps, we would get,

p-value = 0.107622

The p-value is 0.107622.

Please rate the answer. Thank you.