Suppose a subdivision on the southwest side of Denver, Colorado, contains 1,500 houses. The subdivision was built in 1983. A sample of 120 houses is selected randomly and evaluated by an appraiser. If the mean appraised value of a house in this subdivision for all houses is $229,000, with a standard deviation of $8,700, what is the probability that the sample average is greater than $230,500? Appendix A Statistical Tables. (Round the values of z to 2 decimal places. Round your answer to 4 decimal places.)
µ = 229000, σ = 8700, n = 120
P(X̅ > 230500) =
= P( (X̅-μ)/(σ/√n) > (230500-229000)/(8700/√120) )
= P(z > 1.89)
= 1 - P(z < 1.89)
Using excel function:
= 1 - NORM.S.DIST(1.89, 1)
= 0.0294
Suppose a subdivision on the southwest side of Denver, Colorado, contains 1,500 houses. The subdivision was...
Suppose a subdivision on the southwest side of Denver, Colorado, contains 1,500 houses. The subdivision was built in 1983. A sample of 100 houses is selected randomly and evaluated by an appraiser. If the mean appraised value of a house in this subdivision for all houses is $227,000, with a standard deviation of $8,500, what is the probability that the sample average is greater than $229,000?