Answer: ± 1.96
Step-by-step explanation:
Given the following :
Mean (m) time spent = 11.85
Standard deviation = 4 minutes
Since the population of site visits is Normally distributed, Hence, the test statistic will follow a normal distribution :
The test the hypothesis that mean time has changed at 0.05 confidence interval
Normal distributions have a mean value of 0 and standard deviation of 1
Using a two tailed test At 0.05 confidence interval ;
Using the critical value calculator, which in general under normal distributions :
0.05% confidence interval for a two tailed test is
± 1.96
Start with

Add 2 to both sides:

Divide both sides by 7:

Which is true if

If we choose the positive alternative, we have

Otherwise, we have

Answer:
choice d
Step-by-step explanation:
I hand this question
Answer:
24.
Step-by-step explanation:
The is the number of permutations of 3 digits from 4
= 4P3
= 4! / (4- 3)!
= 4 *3 *2 *1 / 1!
= 24/1
= 24.