Answer:
554 executives should be surveyed.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Z-table as such z has a p-value of 
.
That is z with a pvalue of 
, so Z = 1.96.
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
Standard deviation of 3 hours.
This means that 
The 95% level of confidence is to be used. How many executives should be surveyed?
n executives should be surveyed, and n is found with 
. So
Rounding up:
554 executives should be surveyed.
Answer:
x=16°
Step-by-step explanation:
5*x-30=2*(x+18)
For the second, I'd say it is:
5*x-30=2*x+18
Let's solve both.
5*x-30=2*(x+18)
5x-30=2x+36
3x=66
x=22
5*x-30=2*x+18
3x+48
x=16°
Answer:
First, we have rounded numbers A and B, and we know that:
A + B = 11000
A - B = 3000
Now we can solve this system of equations as:
Isolating one variable in one of the equations, i will choose A in the second equation:
A = 3000 + B.
Now we can replace this into the other equation:
3000 + B + B = 11000
2*B = 11000 - 3000 = 8000
B = 8000/2 = 4000
and:
A - 4000 = 3000
A = 3000 + 4000 = 7000.
But remember that our original numbers are not exactly whole numbers, they are rounded up, so we could write them as:
A = 6999.8 (that would be rounded up to 7000)
B = 3999.7 (that would be rounded up to 4000)
The sum is:
A + B = 10999.5 (notice that this would be rounded up to 11000)
A - B = 3000.1 (this would be rounded down to 3000)
Answer:
45
Step-by-step explanation:
90+2x=180
2x=180-90
2x=90
x=90/2
x=45
