A medical laboratory tested 8 samples of human blood for acidity on the pH scale, with the results below. 7.1βββ 7.5βββ 7.5βββ 7.6βββ 7.3βββ 7.2βββ 7.3βββ 7.2 a. Find the mean and standard deviation. b. What percentage of the data is within 3 standard deviations of the mean?
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Step 1
The mean is the sum of all the values divided by the number of values. Mean = (7.1 + 7.5 + 7.5 + 7.6 + 7.3 + 7.2 + 7.3 + 7.2) / 8 Mean = 58.7 / 8 Mean = 7.3375 Next, we need to find the standard deviation. To do this, we first find the variance, which is the Show moreβ¦
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