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3 years ago

A bulb after certain testing had a life of 25 months. The standard deviation based on this sample of size one is

Mathematics

1 answer:

lapo4ka [179]3 years ago

8 0

Answer:

<h2>25 months</h2>

Step-by-step explanation:

Using the formula for calculating the standard error of the mean to get the standard deviation. The standard error of the mean is expressed as;

SE = S/√n where;

S is the standard deviation

n is the sample size

Given SE = 25 months and n = 1, on substituting this parameters into the formula, we will have;

25 = S/√1

25 = S/1

cross multiply

S = 25*1

S = 25 months

<em>Hence the standard deviation based on the sample is 25 months</em>

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Answer:

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Step-by-step explanation:

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completing the squares:

$\bf x^2+y^2+x+y=12\Rightarrow (x+1/2)^2-1/4+(y+1/2)^2-1/4=12\Rightarrow\\\\\Rightarrow (x+1/2)^2+(y+1/2)^2=12+1/2\Rightarrow (x+1/2)^2+(y+1/2)^2=25/2$

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