SOLUTION: Find the standard deviation for the given data. The manager of an electrical supply store measured the diameters of the rolls of wire in the inventory. The diameters of the roll

Algebra.Com
Question 202195: Find the standard deviation for the given data.
The manager of an electrical supply store measured the diameters of the rolls of wire in the inventory. The diameters of the rolls (in m) are listed below. Round results to four decimal places.
0.202 0.426 0.349 0.365 0.669 0.427 0.569
A) 1.2917
B) 1.4310
C) 0.365
D) 0.1523

I came up with like .141 or something, how do i solve this?
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
First sort the numbers into ascending order (from least to greatest):
0.202,0.349,0.365,0.426,0.427,0.569,0.669


Now let's find the mean. So add up all of the numbers and divide the sum by the number of numbers (which in this case is 7).


So the mean is 0.42957



Use this formula to find the Standard Deviation:

Standard Deviation: where is the average, is the ith number, and is the number of numbers

So we can replace N with 7



Subtract to get 6



Replace with 0.42957



Expand the summation (replace each with the respective number)




Subtract the terms in the parenthesis



Square each term



Add up all of the terms



Multiply



Take the square root



So the standard deviation is


which rounds to 0.1523


So the answer is D) 0.1523
RELATED QUESTIONS

the credit manager of large department store claims that the mean balance for the store... (answered by oscargut)
The piston diameter of a certain hand pump is 0.5 inch. The manager determines that the... (answered by CPhill)
If the manager of a paint supply store wants estimate the mean amount of paint in a... (answered by stanbon)
Six different second-year medical students at Bellevue Hospital measured the blood... (answered by Boreal)
The diameters of oranges found in the orchard of an orange farm follow a normal... (answered by ewatrrr)
(b) The mean of the data is 4.9 days with a standard deviation of 3.1 days. The parking... (answered by Boreal)
Help Please? Find the standard deviation for the given data. The pH of a patients... (answered by t0hierry)
Help Please! Last question and really need help... Find the standard deviation for the... (answered by t0hierry,stanbon)
The manager of the Portland Electronics store is concerned that his suppliers have been... (answered by stanbon)