In Exercise 8.69, you found a 95% confidence interval for the mean amount of all venture-capital investments in the fiber optics business sector to be from $5.389 million to $7.274 million. Obtain the margin of error by

a. Taking half the length of the confidence interval.

b. Using Formula 8.1.

Exercise 9.69

Consider a one-mean z-test. Denote z₀ as the observed value of the test statistic z. If the test is right-tailed, then the P-value can be expressed as P(z ≥ z0). Determine the corresponding expression for the P-value if the test is

Formula 8.1

The margin of error for the estimate of μ is z_α/2 · σ/ √n, which is denoted by the letter E. Thus,

FORMULA 8.1 Margin of Error for the Estimate of The margin of error for the estimate of is Za/2.0/n, which is denoted by the letter E. Thus, E = Za/2.0/n.