Answer:
Step-by-step explanation:
Add all 4 sides to get perimeter so the first one is 9+9+2+2=22cm
the area is length x width so the first one is 9 x 2 =18cm ^2
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!
You would do tan<span>Ɵ = 9/12
tan^-1(9/12) = </span><span>Ɵ
</span><span>Ɵ = 36.87 degress
make sure your calculator is in degree mode
</span>
Now cos⁻¹(0.7) is about 45.6°, that's on the first quadrant.
keep in mind that the inverse cosine function has a range of [0, 180°], so any angles it will spit out, will be on either the I quadrant where cosine is positive or the II quadrant, where cosine is negative.
however, 45.6° has a twin, she's at the IV quadrant, where cosine is also positive, and that'd be 360° - 45.6°, or 314.4°.
now, those are the first two, but we have been only working on the [0, 360°] range.... but we can simply go around the circle many times over up to 720° or 72000000000° if we so wish, so let's go just one more time around the circle to find the other fellows.
360° + 45.6° is a full circle and 45.6° more, that will give us the other angle, also in the first quadrant, but after a full cycle, at 405.6°.
then to find her twin on the IV quadrant, we simply keep on going, and that'd be at 360° + 360° - 45.6°, 674.4°.
and you can keep on going around the circle, but only four are needed this time only.
