Answer:
a.1.90 years
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 Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
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.
In this question:

So

So the correct answer is:
a.1.90 years
Answer:
Step-by-step explanation:
As per given information there are 18000 CCTV cameras in the area of 783.8 square kilometers
To find the average number of cameras you divide the number by the area.
The average number of CCTV cameras per square kilometer in NYC = 18000/783.8 = 22.9650421026 ≈ 23
It should be rounded up if taking approximate number
Yes you can have as many equal signs as you need and the approximately equal sign in the same equation.
Answer:
A: This polynomial has a degree of 2 , so the equation 12x2+5x−2=0 has two or fewer roots.
B: The quadratic equation 12x2+5x−2=0 has two real solutions, x=−2/3 or x=1/4 , and therefore has two real roots.
Step-by-step explanation:
f(x) = 12x^2 + 5x - 2.
Since this is a quadratic equation, or a polynomial of second degree, one can easily conclude that this equation will have at most 2 roots. At most 2 roots mean that the function can have either 2 roots at maximum or less than 2 roots. Therefore, in the A category, 2nd option is the correct answer (This polynomial has a degree of 2 , so the equation 12x^2 + 5x − 2 = 0 has two or fewer roots).
To find the roots of f(x), set f(x) = 0. Therefore:
12x^2 + 5x - 2 = 0. Solving the question using the mid term breaking method shows that 12*2=24. The factors of 24 whose difference is 5 are 8 and 3. Therefore:
12x^2 + 8x - 3x - 2 = 0.
4x(3x + 2) -1(3x+2) = 0.
(4x-1)(3x+2) = 0.
4x-1 = 0 or 3x+2 = 0.
x = 1/4 or x = -2/3.
It can be seen that f(x) has two distinct real roots. Therefore, in the B category, 1st Option is the correct answer (The quadratic equation 12x2+5x−2=0 has two real solutions, x=−2/3 or x=1/4 , and therefore has two real roots)!!!
Answer:
B. 30
Step-by-step explanation:
2m^2 + 12
m = 3
2(3)^2 + 12
3 squared is 9
2(9) + 12
2 times 9 is 18
18 + 12 = 30
2m^2 + 12 = 30
Answer:
Not proportional
Step-by-step explanation:
3/6=1/3
14/28=1/2
16/32=1/3
17/34