Answer:
probability at least one zero is 0.3439
Step-by-step explanation:
given data
last four digits = randomly selected
to find out
probability that for one such phone number the last four digits include at least one 0.
solution
we know there are total 10 digit
so we first find probability of non zero digit i.e.
Probability ( non zero ) = 9 /10 = 0.9
and now we find probability of none of digit zero only event happen n= 4 time in a row by multiplication rules i.e
Probability ( none zero in 4 digit ) = 
Probability ( none zero in 4 digit ) = 
Probability ( none zero in 4 digit ) = 0.6561
so we can say probability at least one zero = 1 - Probability ( none zero in 4 digit )
probability at least one zero = 1 - 0.6561
probability at least one zero is 0.3439
Answer:
His actual score is 15
Step-by-step explanation:
Here, we are interested in calculating Wayne’s actual score on the ACT
when we say the scores have being standardized, it means the score was reported in terms of the z-score and not the initial raw scores.
Now, mathematically, for the scores to have a negative z-score, it means it is actually below the mean.
The formula for the z-score or standard score is given below;
z-score = (x - mean)/SD
where in this case, x = ? which is the score we are looking for , z-score = -0.5 , mean score = 18 and standard deviation of the scores = 6
So, substituting these values into the z-score equation, we have;
-0.5 = (x-18)/6
x-18 = 6(-0.5)
x -18 = -3
x = -3 + 18
x = 15
Answer:
The answer should be x - 36
Step-by-step explanation:
We can break down the number 6647 into:
6647=6000+600+40+7
The first 6 in the number is in the thousands place (6,000), and the second 6 is in the hundreds place (600).
The first 6 is 10 times greater than the second one.
If you multiply 2x2 you get 4 and multiply another 2 which is 8. Two answers are 8 and 2x2x2.
