Explanation:
To find the z-value corresponding to a significance level of 0.1388 in a two-tailed test, we need to find the critical values for the test.
Assuming a normal distribution, we can use a standard normal distribution table or calculator to find the critical values.
The significance level for a two-tailed test is split equally between both tails. Therefore, we need to find the z-value that corresponds to a tail area of (1 - 0.1388)/2 = 0.4306.
Using a standard normal distribution table or calculator, we can find that the z-value that corresponds to a tail area of 0.4306 is approximately 1.761.
Therefore, the z-value corresponding to a significance level of 0.1388 in a two-tailed test is +/- 1.761.