The minimum sample size needed in the research of systolic blood pressure is 68.
Given standard deviation=25 mm Hg, confidence level=90%, Estimation =5 mm Hg.
We have to first find the level of alpha which is known as error.
α=(1-0.9)/2
=0.05
Now we have to find z in the z table as such z has a p value of 1-α,that is z with a p value of 1-0.05
=0.95 ,so Z=1.645.
now finding the margin of error, which is as under:
in which st is standard deviation and the n is sample size of population.
By assuming the standard deviation of 25 mm Hg we get values as under:
n is sample size.
dividing both sides by 5
squaring both sides we get
n=67.65.
Hence the sample size needed by the researcher is 68.
Learn more about margin of error at brainly.com/question/24289590
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The given question is incomplete as it should includes :
standard deviation= 25mm Hg
Confidence level=90%
Estimation 5 mm Hg of u.
Apex? I just did got this question and I put
g - 4
and got it right ✌️
Step-by-step explanation:
Consider the left-hand side:
Ok if you look at the first to equations carefully you will see that 2 things have changed between the 2. the "+c" is now "-c" and the "10" is now "3"
if we think about it you will see that c=7. well how do we know. when c or 7 was taken away from the problem it left you with 3
so that means a+b=3
we dont need to know what the exat value of a or b is.
so a+b +3c
(3) + 3(7)
3 + 21
24
a+b+3c=24