Answer:
Option A:
x^2 + (y - 2)^2 = 9
Step-by-step explanation:
We know that the equation for a circle centered in the point (a, b) and of radius R is given by:
(x - a)^2 + (y - b)^2 = R^2
So the first thing we need to find is the center of the circle.
We can see that the center is at:
x = 0
y = 2
Then the center is at the point (0, 2)
Now we want our circle to pass through point 2, located at a distance of 2 units from the radius of the first circle.
So the distance between the center and point 2 is 2 units plus the radius of the smaller circle:
And the radius of the smaller circle is one unit.
Then, the radius of a circle centered at (0, 2) that passes through point 2 is:
R = 1 + 2 = 3
Then we have a circle centered at (0, 2) and of radius R = 3
Replacing these in the equation for a circle we get:
(x - 0)^2 + (y - 2)^2 = 3^2
x^2 + (y - 2)^2 = 9
The correct option is A
Answer:
i think its 3/8 because if 5/8 are male the rest are female so you de 8/8 - 5/8 and you will get 3/8 but i dunno why it says about the aquariaum when the question is about how many female staff therer are
Answer:
C. class number and painting preference.
Step-by-step explanation:
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.