A certain lottery has 39 numbers. In how many different ways can 6 of the numbers be selected? (Assume that order of selection is not important.) There are different ways the numbers can be selected. (Simplify your answer.) C...

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The scores of a test for an engineering class of 30 students are shown here. (Due to the nature of this problem, do not use rounded intermediate values in your calculations-including answers submitted in WebAssign.) Scores: 81, 54, 55, 56, 96, 86, 98, 61, 90, 52, 92, 76, 66, 84, 79, 70, 71, 88, 62, 74, 53, 65, 55, 78, 79, 58, 60, 72, 51,80 (a) Determine the frequency (f), midpoint (x), and xf for each range and fill in the table below. (First, organize the scores into the following ranges: 50-59, 60-69, 70-79, 80-89, and 90-99.) (b) Using the following equation, determine the mean value (x) and fill in the table below. Σ(XA) n X = (c) Calculate (x − x) for each range and fill in the table below. (d) Calculate (x - x)²f for each range and fill in the table below. Range Frequency f Midpoint x 50-59 60-69 70-79 80-89 90-99 S = Enter a number. S = (e) Using the following equation, compute the standard deviation of the class scores. Σ(x-x) ²f n - 1 Σ(x-x) ²4 n - 1 = xf 29 X X - X (x - x)²f

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