Answer:
a) To determine the minimum sample size we need to use the formula shown in the picture 1.
E is the margin of error, which is the distance from the limits to the middle (the mean) of the confidence interval. This means that we have to divide the range of the interval by 2 to find this distance.
E = 0.5/2 = 0.25
Now we apply the formula
n = (1.645*0.80/0.25)^2 = 27.7 = 28
The minimum sample size would be 28.
b) To answer the question we are going to make a 90% confidence interval. The formula is:
(μ - E, μ + E)
μ is the mean which is 127. The formula for E is shown in the picture.
E = 0.80*1.645/√8 = 0.47
(126.5, 127.5)
This means that the true mean is going to be contained in this interval 90% of the time. This is why it doesn't seem possible that the population mean is exactly 128.
The general formula for geometric series is tn = a×rⁿ⁻¹. In this question, a (or a1) is 3, and r is 1.1, therefore the first ten terms would be 3×1.1⁰ (3) , 3×1.1¹ (3.3), 3×1.1² (3.63) and so on up until you get to 3×1.1⁹ or 7.07.
Answer:
5956 ft
Step-by-step explanation:
If we designate the points at the bases of the skyscrapers as A and B, and the top of skyscraper B as point T, then triangle ABT is a right triangle with angle B = 90° and angle A = 13.7°.
The definition of the tangent function tells us ...
tan(A) = BT/AB
Solving for AB, we find ...
AB = BT/tan(A) = (1452 ft)/tan(13.7°)
AB ≈ 5956 ft
The skyscrapers are about 5956 feet apart.
Answer:
ft
Step-by-step explanation:
Use the Pythagorean theorem to find the unknown side in any right triangle,
Essentially, look at it as if it was flat.
a is half of the diameter, so 2 ft.
b is your height, 9ft
