Question

steps and answer please

Bue in 11 hours, 15 minutes. Due Sat 11/09/2014 11:59 p Assume that the readings at freezing on a batch of thermometers are normally distributed with a mean of 0°C and a standard deviation of 1.00°C. A single thermometer is randomly selected and tested. Find the probability of obtaining a reading between -2.957°C and 2.723°C. P( - 2.957 < < < 2.723) =

Answer 1

Solution

Back-up Theory

If Z ~ N(0, 1), i.e., Standard Normal Distribution

Probability values for the Standard Normal Variable, Z, can be directly read off from

Standard Normal Tables ………………………………………………......................…..…….......…………… (1a)

or can be found using Excel Function: Statistical, NORMSDIST(z) which gives P(Z ≤ z) ….......................(1b)

Now, to work out the solution,

P(- 2.957 < Z < 2.723)

= P(Z < 2.723) - P(Z < - 2.957)

= 0.9968 – 0.0016 [vide (1b)]

= 0.9952   Answer

DONE