Answer:
0.2.
Step-by-step explanation:
To determine the p-value for the test, we need to compare the standardized test statistic to the critical value associated with the chosen level of significance. In this case, the null hypothesis is 0:=0.4 and the alternative hypothesis is :≠0.4.
Since the test statistic is given as 1.28, we need to find the corresponding area under the standard normal distribution curve. This area represents the probability of observing a test statistic as extreme as 1.28 or more extreme, assuming the null hypothesis is true.
To find the p-value, we can use a standard normal distribution table or a calculator. The p-value is the probability of observing a test statistic as extreme as 1.28 or more extreme, in both tails of the distribution.
Looking up the value of 1.28 in a standard normal distribution table, we find that the area to the right of 1.28 is approximately 0.1003. Since we are interested in both tails, we need to multiply this probability by 2.
Therefore, the p-value is approximately 2 * 0.1003 = 0.2006.
Comparing the calculated p-value to the given options, we can see that the closest value is a. 0.2.
