Salary of a travel management professional. According to the most recent Global Business Travel Association (GBTA) survey, the average base salary of a U.S. travel management professional is \(94,000. Assume that the standard deviation of such salaries is \)30,000. Consider a random sample of 50 travel management professionals and let χ¯ represent the mean salary for the sample.

  1. What isμχ¯?
  2. What isσχ¯?
  3. Describe the shape of the sampling distribution ofχ¯.
  4. Find the z-score for the valueχ¯=86,660
  5. FindPχ¯>86,660.

Short Answer

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Step by step solution

01

(a) The data is given below

The calculation is given below:

Given,

μ=94,000σ=30,000n=50

μχ¯=μ0=94000μχ¯=94000

02

(b) The data is given below

The calculation is given below:

σχ¯=σn=30,00050=4242.640687124242.6407

σχ¯=4242.6407

03

(c) The data is given below

The calculation is given below:

As here n30

As a result, the sample size is sufficient to follow the normal distributions. As a result, the distribution's form is normal.

The chart is given below:

04

(d) The data is given below

The calculation is given below:

Zscore=χ-μσ/n


χ=86660μ=94000n=50

Zscore=86660-940004242.6407=-1.73

05

(e) The data is given below

The calculation is given below:

Pχ¯>8660=1-Pχ¯<8660=1-Pχ¯-μχ¯σχ¯<8660-940004242.6407=1-PZ<-1.73

Standard normal table:

=1-0.9581848=0.04181520.0418Pχ¯>86660=0.0418

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