The following table shows the salaries of the employees of companies A and B. В. Salary () 5,001-10,000 10,001-15,000 15,001-20,000 20,001-25,000 25.001-30,000 30,001-35,000 Company A 12 43 10 7. 3 Frequency 5. 3 3 Company B 7. 38 24 1. Find the standard deviations of the salaries of the employees in each company. (Give your answers correct to 3 significant figures) 2. Hence, which company offers more uniform salaries to its employees?

(a) The population 3, 4, 9, 14, and 20 has a mean of 10 and a standard deviation of 6.356. The z-scores for each of the five data values are  z3 ≈ −1.101, z4 ≈ −0.944, z9 ≈ −0.157, z14 ≈ 0.629, and z20 ≈ 1.573.  Find the mean and the standard deviation of these z-scores. mean       standard deviation   (b) The population 2, 6, 12, 17, 22, and 25 has a mean of 14 and a standard deviation of 8.226. The z-scores for each of the six data values are  z2 ≈ −1.459, z6 ≈ −0.973, z12 ≈ −0.243, z17 ≈ 0.365, z22 ≈ 0.973, and z25 ≈ 1.337.  Find the mean and the standard deviation of these z-scores. mean       standard deviation       (c) Use the results of part (a) and part (b) to make a conjecture about the mean and standard deviation of the z-scores for any set of data. The mean of the z-scores is always 1, and their standard deviation is 0. The mean of the z-scores is always 1 more than the standard deviation.     The mean and standard deviation of z-scores are never the same.…

The following table shows the number of people that have either 0, 1, 2 or 3 cars registered in their name, from a sample of 311 people. x n 0 93 1 91 2 60 3 67 (a) Find the mean number of cars owned for this sample. Give your answer to at least 2 decimal places. (b) Find the standard deviation of cars owned for this sample. Give your answer to at least 2 decimal places.

Calculate the mean and standard deviation for the two variables separately.

Directions: Compute the total returns, the average of returns, and the standard deviation of the following stocks: 1) 2) EGRH Inc. MP, Ltd. AVERAGE OF STOCK RETURN YEA AVERAGE OF RETURNS (x) YEAR STOCK RETURN PRICE (x₁) PRICE RETU Jan-2021 Po Feb-2021 P8.6 Jan-2021 PO. Feb-2021 PO.090 Mar-2021 P0.097 Apr-2021 PO.189 May-2021 PO.164 Mar-2021 P9.14 Apr-2021 P13.30 May-2021 P13 Jun-2021 P60 Jul-2021 16.94 Jun-2021 P0.495 Jul-2021 PO.28 Aug-2021 PO Sep-2021 90 Aug-202 P13.70 Sep-2 P14.88 Oct-2021 0.375 Oct 21 P15.30 Nov-20 PO.325 N2021 P14.30 Dec-2 PO.330 ec-2021 P15.52 3) SD (8) GSM Inc. YEAR Jan-2021 P57. Feb-2021 P52.90 Mar-2021 P50.95 Apr-2021 P58.25 May-2021 P74.05 Jun-2021 P94.75 Jul-2021 P85.0 Aug-2021 P10 Sep-2021 P 00 Oct-2021 01.00 Nov-2021 100.40 Dec-202 P113.80 SD (8) = STOCK RETURN PRICE (x₁) AVERAGE OF RETURNS -x)² SD (8) = ACEE, Inc. YEAR STOCK RETURN PRICE (x₁) Jan-2021 P13.56 Feb-2021 P20.80 Mar-2021 P22.50 Apr-2021 P18.90 May-2021 P17.00 Jun-2021 P18.76 Jul-2021 P16.38…

The reading speed of second grade students in a large city is approximately​ normal, with a mean of 91words per minute​ (wpm) and a standard deviation of 10 wpm. Complete parts​ (a) through​ (f).