Answer:
b. Hannah is likely to be incorrect because 9 is not contained in the interval.
Step-by-step explanation:
Hello!
Hannah estimated per CI the difference between the average time that people spend outside in southern states and the average time people spend outside in northern states.
The CI is a method of estimation of population parameters that propose a range of possible values for them. The confidence level you use to construct the interval can be interpreted as, if you were to calculate 100 confidence interval, you'd expect that 99 of them will contain the true value of the parameter of interest.
In this example, the 99%CI resulted [0.4;8.0]hs
Meaning that with a 99% confidence level you'd expect the value of the difference between the average time people from southern states spend outside than the average time people from northern states spend outside is included in the interval [0.4;8.0]hs.
Now, she claims that people living in southern states spend 9 more hours outside than people living in northern states, symbolized μ₁ - μ₂ > 9
Keep in mind that if you were to test her claim, the resulting hypothesis test would be one-tailed
H₀: μ₁ - μ₂ ≤ 9
H₁: μ₁ - μ₂ > 9
And that the calculated Ci is tow-tailed, so it is not valid to use it to decide over the hypotheses pair. This said, considering that the calculated interval doesn't contain 9, it is most likely that Hannah's claim is incorrect.
I hope this helps!
Answer:

Step-by-step explanation:
When taking a square root and making it a radical, we need to list out it's factors and find which one we can take the square root of.
The factors of 40 are:
1, 2, 4, 5, 8, 10, 20, 40.
Out of these, we need to look for one that we can find the square root of.
We know that the square root of 4 is 2.
Therefore, we can make
into
.
The square root of 4 is 2. Therefore, we can put that outside the radical.
.
Hope this helped!
Answer:
its B
Step-by-step explanation:
If 68 is a prime number, then the only factors it has are 1 and 68.
If it has any other factors besides 1 and 68, then it's NOT prime.
Right away, without any higher math, you can look at just the last digit
in 68 . The last digit is '8'. That tells you that '68' is an even number,
and THAT tells you that '2' must be one of its factors. So '68' is not a
prime number.
The factors of 68 are 1, 2, 4, 17, 34, and 68 .
68 has four more factors besides 1 and 68, so it's not a prime number.