Answer: 34 degrees of freedom should be used to find the p-value of the test .
Step-by-step explanation:
Degrees of Freedom relates to the maximum number of independent values, that have independence to vary in the sample.
Given : When testing the difference between two population means and the population variances are unknown and unequal, the degrees of freedom are calculated as 34.7.
But degree of freedom must be an integer , so we find the greatest integer less than equal to the calculated degree of freedom.
i.e. [df]=[34.7]= 34
Thus , 34 degrees of freedom should be used to find the p-value of the test .
X= 7 1/3
Explanation- Take 72 and subtract 50 from that giving you 22. Then take 22 and divide it by 3 to get 7.3333333333333 (repeats) or 7 1/3
Answer:
37044 different combinations of 4 movies can he rent if he wants at least one comedy
Step-by-step explanation:
The order in which the movies are selected is not important, so we use the combinations formula to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.
How many different combinations of 4 movies can he rent if he wants at least one comedy
The easier way to solve this is subtract the total from the number of combinations with no comedies.
Total:
4 movies from a set of 14 + 19 = 33. So
No comedies:
4 movies from a set of 19.
At least one comedy:
40920 - 3876 = 37044
37044 different combinations of 4 movies can he rent if he wants at least one comedy