In a quality control check of a drug dispenser a sample of 1

In a quality control check of a drug dispenser, a sample of 16 drug droplets was analyzed: more in detail, the volume (in pL, picoliters) of each droplet was measured. The resulting sample mean and sample standard deviation were 38.3 and 2.5 respectively. The droplet volume is expected to be normally distributed with µ = 40.0 pL (box theory).

(a) Determine the uncertainty on the sample standard deviation, and express the result of the measurement (x ± s) by using the appropriate number   of significant digits;

(b) Formulate a null hypothesis (H_o ) to assess the quality of the drug dispenser;

(c) State which statistical test is to be used;

(d) Discuss the validity of H_o ;

(e) Discuss the validity of H_o provided that the additional information that the normal distribution has = 1.8 pL is given.

Solution