Use a t-distribution to answer this question. Assume the samples are random samples from distributions that are reasonably norma
lly distributed, and that a t-statistic will be used for inference about the difference in sample means. State the degrees of freedom used. Find the proportion in a t-distribution less than −1.4 if the samples have sizes n1=30 and n2=40.
Enter the exact answer for the degrees of freedom and round your answer for the area to three decimal places.
Using the t-distribution, it is found that the proportion in a t-distribution less than −1.4 if the samples have sizes n1=30 and n2=40 is of 0.083.
<h3>How to find a proportion in a t-distribution?</h3>
The proportion is found using a calculator, with three inputs:
The tail of the test, if it is left, right, or two-tailed.
The test statistic.
The amount of degrees of freedom.
In this problem, we have a left-tailed proportion, as we want the proportion that is less than a value, with test statistic t = -1.4 and 30 + 40 - 2 = 68 df, hence the proportion is of 0.083.
