Question

need help answering these questions please

Listed below are foot lengths in inches for 11 randomly selected people taken in 1988. Find the range variance, and standard deviation for the given sample data. Include appropriate units in the results are the statistics representative of the current population of all people? 92 9.4 104 98 104 98 85 97 9.5 10.1 86 The range of the sample data is (Type an integer or a decimal. Do not round.) The standard deviation of the sample data is Round to two decimal places as needed The variance of the sample data is Round to two decimal places as needed Are the statistics representative of the current population of all people? O A. The statistics are representative because they are taken from a random sample OB. Since the measurements were made in 1968, is not necessarily representative of the population today. OC. The statistics are representative because the standard deviation of the sample data is less than 1. OD. The statistics are not representative because a smaler sample is needed to represent the population

Answer 1

Maximum value = 10.4

Minimum value = 8.5

Range = Maximum value - Minimum value = 10.4 - 8.5

Range = 1.9

To find standard deviation we use the following formula 2 (2:-X) n-1 We will compute this formula in 4 steps. Step 1: Find the mean. (x In this example: X = 9.5818. (use this calculator for step by step explanation on how to find mean). Step 2: Create the following table. data 9.2 9.4 10.4 9.8 10.4 data-mean (data - mean) -0.3818 0.14577124 -0.1818 0.03305124 0.8182 0.66945124 0.2182 0.047611240000001 0.8182 0.66945124 0.2182 0.047611240000001 -1.0818 1.17029124 0.1182 0.01397124 -0.081799999999999 0.0066912399999999 0.5182 0.26853124 -0.9818 0.96393124 9.8 8.5 9.7 9.5 10.1 8.6 Step 3: Find the sum of numbers in the last column to get. (2-x) – 4 = 4.0364

Step 4: Calculate o using the above formula. (– X)" 4.0364 0.6353 n-1 V 11-1

The standard deviation of the sample data is 0.64

Variance = Standard Deviation^2 = 0.6353^2 = 0.4036

The variance of the sample data is = 0.40

B. Since the measurements were made in 1988 it is not necessarily representative of the population today.