Ms. Chemistry gave a 10-item test in Statistics to eight students and obtained the following scores: 6, 4, 3, 6, 5, 8, 4, 5 Variance = SD

In an effort to counteract student cheating, the professor of a large class created four versions of a midterm exam, distributing the four versions among the 344 students in the class, so that each version was given to 86 students. After the exam, the professor computed the following information about the scores (the exam was worth 200 points): Group Sample Sample Sample size mean variance Version A Version B Version C Version D 86 150.3 420.3 86 155.7 352.0 86 148.5 479.1 86 158.8 369.9 Send data to calculator Send data to Excel The professor is willing to assume that the populations of scores from which the above samples were drawn are approximately normally distributed and that each has the same mean and the same variance. Answer the following, carrying your intermediate computations to at least three decimal places and rounding your responses to at least one decimal place. (a) Give an estimate of this common population variance based on the variance of the sample means given. (b)…

If you have samples of n₁ = 22 and n₂ = 19, in performing the pooled-variance t test, how many degrees of freedom do you have? You have degrees of freedom.

Kindly answer part i. & ii. only.

A sample of n = 10 has s = 3. What are the correct values for S.S. and s2? SS=44;sampleS.D.=3 SS = 81; sample variance = 9 SS = 30; sample variance = 4 SS=27;sampleS.D.=2

We are interested in determining whether or not the variances of the sales at two music stores (A and B) are equal. A sample of 16 days of sales at store A has a sample variance of 20 while a sample of 26 days of sales from store B has a sample variance of 30. The test statistic is

. ​If one sample has n = 5 scores with SS = 40 and a second sample has n = 5 scores with SS = 20, then what is the pooled variance

What are the values for SS and variance for the following sample of n = 3 scores? Sample:  8, 5, 2

. What are the values of SS and variance s? for the following sample of n=3 scores? Sample: 1, 4, 7

If you have samples of n1=19 and n2=24​, in performing the​ pooled-variance t​ test, how many degrees of freedom do you​ have?