Answer: 17.89
Step-by-step explanation:
In binomial distribution, the standard deviation is given by :-

As per given , we have
The number of vouchers in the sample with errors is denoted by x.
p= 0.20 , n = 2000
Then , 

Hence, the standard deviation of x is 17.89.
Answer:
Usually there are the variables x y z but it doesn't matter what they are.
Step-by-step explanation:
First choose your first variable to solve. Find x by putting all the numbers and variables to one side.
once you found x substitute the answer for x in all the equations. Next find y and substitute your answer in all the equations again.
Once you have solved 2 variables then you are able to solve z.
If you have questions please feel free to ask in the comments below.
Answer:
no solution
Step-by-step explanation:
1/2(4x+14)=2(x-7)
Multiply both sides by 2.
4x + 14 = 4(x - 7)
4x + 14 = 4x - 28
Subtract 4x from both sides.
14 = -28
Since 14 = -28 is a false statement, there is no solution for this equation.
Answer: no solution
Let's try the actual solution of the system
<span>y = –2x + 1
y = –2x – 3
Note that the slopes of the graphs of these two lines are the same: -2.
That means that the lines are parallel to one another.
Only the y-intercepts (1 and -3) are different.
Since the 2 lines never intersect, the system has no solution.
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