Answer:
(3.8, 6.8)
Step-by-step explanation:
Point B:
Has coordinates (x,y)
AB and BC form a 2:3 ratio.
This means that:
We apply this both for the x-coordinate and for the y-coordinate.
x-coordinate:
x-coordinate of A: 3
x-coordinate of C: 5
x-coordinate of B: x
y-coordinate:
y-coordinate of A: 4
y-coordinate of C: 11
y-coordinate of B: y
Thus the correct answer is:
(3.8, 6.8)
Answer:
We would have to take a sample of 62 to achieve this result.
Step-by-step explanation:
Confidence level of 95%.
We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of .
That is z with a pvalue of , so Z = 1.96.
Now, find the margin of error M as such
In which is the standard deviation of the population and n is the size of the sample.
Assume that the standard deviation in the amount of caffeine in 8 ounces of decaf coffee is known to be 2 mg.
This means that
If we wanted to estimate the true mean amount of caffeine in 8 ounce cups of decaf coffee to within /- 0.5 mg, how large a sample would we have to take to achieve this result?
We would need a sample of n.
n is found when . So
Dividing both sides by 0.5
Rounding up
We would have to take a sample of 62 to achieve this result.