has developed a new battery for its portable navigation systems. To help market this system, the company wants to know how long, on average, the batteries last before they burn out. The company tests a random sample of 100 batteries and find that the sample mean is 80 hours, with a sample standard deviation of 20 hour What is the point estimate for the mean lifetime of the batteries

The sample mean (x⁻) = 80 hours is a point estimate for  the mean lifetime of the batteries

Step-by-step explanation:

Explanation:-

Point  Estimate:-

The sample mean (x⁻) is a point estimate of the Population mean 'μ'

Given data

mean of the sample (x⁻) = 80 hours

Therefore The sample mean (x⁻) = 80 hours is a point estimate for  the mean lifetime of the batteries.

and

The sample standard deviation (s) is a point estimate of the Population standard deviation(σ).

Given data

standard deviation of the sample (s) = 20 hours

Therefore The sample standard deviation (s) = 20 hours is a point estimate of the Population standard deviation(σ).

step-by-step explanation:

given that there are two triangles j'k'l' and jkl>

the former is got by dilating the second one.

when drawn on a grid, (graph paper) coordinates of vertices of first triangle is

(6,12)j, (9,6)k and (12,9)l

side jk has length = distance between j and k

=

side j'k'=distance between j' and k'

=

ie j'k'l' has sides 1/3 of that of corresponding sides of jkl.

hence scale factor of 1/3 is used to get j'k'l'from jkl

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step-by-step explanation: