Answer:
The 95% confidence interval for the mean change in blood pressure,
, is 1.744 <
< 2.816
Step-by-step explanation:
The parameters given are;
The number of people in the sample, n = 9
The average drop in blood pressure,
= 2.28 points
The standard deviation, σ = 0.82
The confidence level = 95%
The formula for confidence interval with a known mean is given as follows;

Where:
= z - score at 95% confidence level = 1.96
We therefore have;

Which gives the 95% confidence interval for the mean change in pressure,
, is given as follows;
1.744 <
< 2.816
Hi there!
First, you need to find the quotient of 4 and 13, obviously.
4/13 is equal to roughly 0.308.
Those grouping symbols around it tell you that you need to find the absolute value.
Absolute value is how far away a number is from 0 on a number line. 3, for example has a absolute value of 3, and -6 has an absolute value of 6.
So, the absolute value of 4/13 is about 0.308.
Hope this helps. :)
-Spagoot
Answer:
Since r is the distance from the origin to (x,y), it is the magnitude r=√x2+y2. Alternatively, from the equation (1), one can calculate directly that x2+y2=r2cos2θ+r2sin2θ=r2(cos2θ+sin2θ)=r2.
Step-by-step explanation:
Actually, if you notice that two of the lines are parallel, the answer is x=53!