Question

Find the critical value z Subscript alpha divided by 2 that corresponds to the given confidence level. 80​%

Answer 1

Answer:

$Conf= 0.80$

With the confidence level we can find the significance level:

$\alpha =1-0.8=0.2$

And the value for $\alpha/2=0.1$. Then we can use the normal standard distribution and we can find a quantile who accumulates 0.1 of the area on each tail and we got:

$z_{\alpha/2}= \pm 1.28$

Step-by-step explanation:

For this problem we have the confidence level given

$Conf= 0.80$

With the confidence level we can find the significance level:

$\alpha =1-0.8=0.2$

And the value for $\alpha/2=0.1$. Then we can use the normal standard distribution and we can find a quantile who accumulates 0.1 of the area on each tail and we got:

$z_{\alpha/2}= \pm 1.28$