Answer:
Step-by-step explanation:
So 8 times what is 5?
8 times x=5
x=0.625
Answer:

Step-by-step explanation:
To find x, the following equation is generated given the available information:



Cross multiply


Collect like terms



Answer:
The area of the triangle is of 8 units of area.
Step-by-step explanation:
Answer:
The area of the triangle is of 21 units of area.
Step-by-step explanation:
The area of a triangle with three vertices
is given by the determinant of the following matrix:

In this question:
Vertices (1,0) (5,0) (3,4). So




The area of the triangle is of 8 units of area.
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.