Answer:
d. t distribution with df = 80
Step-by-step explanation:
Assuming this problem:
Consider independent simple random samples that are taken to test the difference between the means of two populations. The variances of the populations are unknown, but are assumed to be equal. The sample sizes of each population are n1 = 37 and n2 = 45. The appropriate distribution to use is the:
a. t distribution with df = 82.
b. t distribution with df = 81.
c. t distribution with df = 41.
d. t distribution with df = 80
Solution to the problem
When we have two independent samples from two normal distributions with equal variances we are assuming that
And the statistic is given by this formula:
Where t follows a t distribution with
degrees of freedom and the pooled variance
is given by this formula:
This last one is an unbiased estimator of the common variance
So on this case the degrees of freedom are given by:

And the best answer is:
d. t distribution with df = 80
missing letter is 2
missing letter is 3
missing letter is 1
Hope it is helpful to you ☺️
Answer:
The mean is 12, The median is 13, The mode is 14, and the range is 8.
The second choice is the correct answer.
Explanation:
- I found the mean by adding up all the numbers and dividing by the number of numbers, or sun divided by count. The sum of the numbers was 132, and the count was 11. I divided 132 by 11 to get 12.
- I listed the numbers in order from least to greatest. The data set was: 7, 8, 10, 12, 12, 13, 13, 14, 14, 14, 15
- I found the median by crossing off the number on each end of the data set, and kept going. For example, I crossed off 8, and then 15, and then 10, and then 14 and so on until I got to the middle number. (Keep in mind, if there are two middle numbers, find the mean of them [add them and divide by two])
- The mode is the number that shows up the most in the data set, so I looked at the data set and saw that 14 showed up 3 times, more times than any other number.
- The range is the difference between the greatest and least number (maximum and minimum) so I just subtracted 15 - 7 to get a difference of 8.
It equals to 65 for the exact answer
Answer:
6 * (m + n)
Step-by-step explanation: