Question

find the critical value ( z_{alpha/2} ) that corresponds to the given confidence level.
87%

( z_{alpha/2} = square ) (round to two decimal places as needed.)

Explanation:

Step1: Calculate α

$\alpha = 1 - 0.87 = 0.13$

Step2: Find α/2

$\frac{\alpha}{2} = \frac{0.13}{2} = 0.065$

Step3: Find cumulative area

Cumulative area = $1 - 0.065 = 0.935$

Step4: Look up z-score

Find z-score for cumulative area 0.935 in standard normal table.

Answer:

1.51