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.
6+(4/5)
=(30/5)+(4/5)
=34/5
Answer:
See explanations below
Explanation:
Vertex of a graph is the lowest point on the curve. The vertex occurs at (1.75, -2.5)
The axis of symmetry is the point on the x axis of the line that cuts through the minimum point. The axis of symmetry occurs at x = 1.75
x intercept is the point where the curve cuts the x axis. The x intercept occurs at x = 0 and x = 2.5
To get the minimum, we will use the formula;
c - b^2/4a
The equation of the curve is expressed as;
(x-0)(x-2.5)
= x (x-2.5)
= x^2 - 2.5x
a = 1, b = -2.5, c = 0
minimum = 0 - (-2.5)^2/4(1)
minimum = -6.25/4
minimum = -1.5625
Minimum value occurs at the base of the parabola. The minimum value of the function is -2.5
y intercept is the point where the curve cuts the y axis. The y-intercept occurs at y = 0.
Answer:
a, b and e
Step-by-step explanation:
Basically using distrabutive property the options distrabute to give the current expression due to signs.