Answer: D) 
Step-by-step explanation:
As per given , we have
Sample size : n= 15
sample mean : 
Sample standard deviation: s= $20
Since population standard deviation is unknown , so we use t-test.
Significance level for 95% confidence : 
Critical t-value : 
[Using students' t-value table]
Required 95% Confidence interval :-
Hence, the required 95% confidence interval for the mean amount its credit card customers spent on their first visit to the chain's new store in the mall assuming that the amount spent follows a normal distribution.:
The answer is B. Hope this helps!
300 - 2x = 146, where x is the number
Subtract 300 from both sides.
-2x = -154
Divide both sides by -2.
x = 77
Answer: a.) 40320
b.) 336
Step-by-step explanation:
since we have 8 possible positions, with 8 different candidates, then there are 8 possible ways of arranging the first position, 7 possible ways of arranging the Second position, 6 ways of arranging the 3rd position, 5 possible ways od arranging the 4th position, 4 possible ways of arranging the 5th position, 3 possible ways of arranging the 6th position, 2 possible ways of arranging the 7th position and just one way of arranging the 8th position since we have only one person left.
Hence, the Number of possible sample space for different 8 positions is by multiplying all the number of ways we have in our sample space which becomes:
8*7*6*5*4*3*2*1 = 40320.
b.) By the sample space we have, since we've been asked ti arrange for only the firat 3 positions, then we multiply just for the first 3ways of choosing the positions, this becomes:
8*7*6 = 336
Answer:
(0,0)
Step-by-step explanation:
We have,
U = { (x,y) : x,y belong to real numbers }
A = { (x,y) : (x,y) is a solution of y=x }
B = { (x,y) : (x,y) is a solution of y=2x }
We need to find the ordered pair (x,y) that belong to A
B.
Let, (x,y) belong to AB
i.e. (x,y) belong to A and (x,y) belong to B
i.e. y = x and y = 2x
i.e. x = 2x
i.e. x = 0
Now, substitute x= 0 in any of the equation say y = x, we get y = 0.
Hence, the ordered pair satisfying AB is (0,0).
