Question

1. (a) What are the first and third quartiles of the standard normal distribution?

2. (b) Using your numerical values from (a), write the equations that give the quartiles of

   the N(μ,σ) distribution in terms of μ and σ.

3. (c) Arsenic is a compound that occurs naturally in very low concentrations. Arsenic blood concentrations in healthy adults are normally distributed with mean μ = 3.2 micro- grams per deciliter (μg/dl) and standard deviation σ = 1.5 μg/dl. Apply your result from (b): what are the quartiles of the distribution of arsenic blood concentrations in healthy adults?

Answer 1