Question

Let x = red blood cell (RBC) count in millions per cubic millimeter of whole blood. For healthy females, x has an approximately normal distribution with mean μ = 3.1 and standard deviation σ = 0.2.

(a) Convert the x interval, 4.5 < x, to a z interval. (Round your answer to two decimal places.)
< z

(b) Convert the x interval, x < 4.2, to a z interval. (Round your answer to two decimal places.)
z <

(c) Convert the x interval, 4.0 < x < 5.5, to a z interval. (Round your answers to two decimal places.)
< z <

(d) Convert the z interval, z < −1.44, to an x interval. (Round your answer to one decimal place.)
x <

(e) Convert the z interval, 1.28 < z, to an x interval. (Round your answer to one decimal place.)
< x

(f) Convert the z interval, −2.25 < z < −1.00, to an x interval. (Round your answers to one decimal place.)
< x <

(g) If a female had an RBC count of 5.9 or higher, would that be considered unusually high? Explain using z values.

Yes. A z score of 14.00 implies that this RBC is unusually high.

No. A z score of −14.00 implies that this RBC is unusually low.    

No. A z score of 14.00 implies that this RBC is normal.

Answer 1