Answer:
<em>The sample mean (x⁻) = 80 hours is a point estimate for the mean lifetime of the batteries</em>
Step-by-step explanation:
<u><em>Explanation:-</em></u>
<u><em>Point Estimate:-</em></u>
The sample mean (x⁻) is a point estimate of the Population mean 'μ'
Given data
mean of the sample (x⁻) = 80 hours
<em>Therefore The sample mean (x⁻) = 80 hours is a point estimate for the mean lifetime of the batteries.</em>
<em>and </em>
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
<em>Therefore The sample standard deviation (s) = 20 hours is a point estimate of the Population standard deviation(σ).</em>
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