Use the given information to find the P-value. Also, use a 0.05 significance level and state the conclusion about the null hypothesis (reject the null hypothesis or fail to reject the null hypothesis).

The test statistic in a left-tailed test is [tex]$z = -1.83$[/tex].

A. 0.0336; reject the null hypothesis
B. 0.9664; fail to reject the null hypothesis
C. 0.0672; reject the null hypothesis
D. 0.0672; fail to reject the null hypothesis



Answer :

To solve the problem, we will follow these steps:

1. Understand the given information:
- The test statistic for the left-tailed test is [tex]\( z = -1.83 \)[/tex].
- The significance level (alpha) is [tex]\( 0.05 \)[/tex].

2. Calculate the P-value:
- The P-value corresponds to the cumulative probability of obtaining a value less than or equal to the test statistic in the standard normal distribution. Given [tex]\( z = -1.83 \)[/tex], we find the P-value as approximately [tex]\( 0.0336 \)[/tex].

3. Decision Rule:
- Compare the P-value with the significance level.
- If the P-value [tex]\( < 0.05 \)[/tex], we reject the null hypothesis.
- If the P-value [tex]\( \geq 0.05 \)[/tex], we fail to reject the null hypothesis.

4. Make the conclusion:
- Since the P-value [tex]\( 0.0336 \)[/tex] is less than the significance level [tex]\( 0.05 \)[/tex], we reject the null hypothesis.

Therefore, the correct interpretation is:
- With a test statistic of [tex]\( z = -1.83 \)[/tex] and a significance level of [tex]\( 0.05 \)[/tex], the P-value is approximately [tex]\( 0.0336 \)[/tex].
- Since [tex]\( 0.0336 \)[/tex] is less than [tex]\( 0.05 \)[/tex], we reject the null hypothesis.

Thus, the answer is:

- [tex]\( 0.0336 \)[/tex]; reject the null hypothesis.

This matches the choice [tex]\( 0.0336 \)[/tex]; reject the null hypothesis.