Answer:
Step-by-step explanation:
Given that a professor sets a standard examination at the end of each semester for all sections of a course. The variance of the scores on this test is typically very close to 300.

(Two tailed test for variance )
Sample variance =480
We can use chi square test for testing of hypothesis
Test statistic = 
p value = 0.0100
Since p <0.05 our significance level, we reject H0.
The sample variance cannot be claimed as equal to 300.
Answer:
The correct answer is an event occurring one or fewer times in 100 times if the null hypothesis is true.
Step-by-step explanation:
For a statistically rare event, its probability is relatively small and the event is very unlikely to occur. Therefore, if an experimental sets equal to 0.01 which is statistically rare, then we can interpret this mathematically as:
p(event) = 0.01 = 1/100
where p(event) is the probability of the event.
In addition, statistically, null hypothesis signifies no major difference between the specified parameters, and any obvious difference that might occur as a result of experimental error. Thus, it can be concluded that the event is occurring one or fewer times in 100 times if the null hypothesis is true.
113.94-42.50+189.73-22.50-70.18= $168.49
LaToya has $168.49 in her checking account
Answer:
-27
Step-by-step explanation:
9(4x – 15)
Substitute 3 for x
9((4)(3) - 15)
Multiply (4)(3) = 12
9 ( 12 - 15 )
Subtract 12 - 15 = -3
9(-3)
Multiply 9(-3) = -27