Answer:
190
Step-by-step explanation:
Data provided in the question:
Confidence level = 99%
Therefore,
α = 1% = 0.01
[ from standard normal table ]
z-value for = 2.58
Margin of error, E = $0.06
Standard deviation, σ = $0.32
Now,
n =
Here,
n is the sample size (or the minimum number of gas stations )
on substituting the respective values, we get
=
=
= 13.76²
= 189.3376 ≈ 190
Hence,
minimum number of gas stations that she should include in her sample is 190
Answer:
101.9 sq ft
Step-by-step explanation:
The figure is missing: find it in attachment.
Here we want to find the lateral surface area of the figure, which is the sum of the areas of all faces.
We have in total 5 faces:
- 1 of them is rectangle with sizes (8.5 ft x 3.3 ft), so its area is
- 1 of them is a rectangle with sizes (3.3 ft x 5.1 ft), so its area is
- 1 of them is a rectangle with sizes (6.8 ft x 3.3 ft), so its area is
- Finally, we have 2 triangular faces (top and bottom), so their area is
where
b = 5.1 ft is the base
h = 6.8 ft is the height (because the triangle is a right triangle)
So the area of the triangle is
So the total lateral surface area of the figure is:
