An analyst is assigned a blind quality control sample of blood containing a drug metabolite. He tests ten separate portions and obtains the following data for the concentration in ug/mL:
25.2
24.8
26.6
27.0
24.0
26.0
25.5
26.3
24.9
23.9
Calculate the population standard deviation and report to three significant figures. Use a spreadsheet or calculator.

Question

Quizplus · Accepted Answer

The population standard deviation is 1.00 ug/mL. This can be calculated using a spreadsheet or calculator. The formula for the population standard deviation is:σ = √(Σ(x - μ)² / N)where:σ is the population standard deviationx is each data pointμ is the population meanN is the number of data pointsIn this case, the population mean is 25.2 ug/mL. The population standard deviation is then:σ = √(Σ(x - 25.2)² / 10) = 1.00 ug/mL

An Analyst Is Assigned a Blind Quality Control Sample of Blood