Since in this case we are
only using the variance of the sample and not the variance of the real population,
therefore we use the t statistic. The formula for the confidence interval is:
<span>CI = X ± t * s / sqrt(n) ---> 1</span>
Where,
X = the sample mean = 84
t = the t score which is
obtained in the standard distribution tables at 95% confidence level
s = sample variance = 12.25
n = number of samples = 49
From the table at 95%
confidence interval and degrees of freedom of 48 (DOF = n -1), the value of t
is around:
t = 1.68
Therefore substituting the
given values to equation 1:
CI = 84 ± 1.68 * 12.25 /
sqrt(49)
CI = 84 ± 2.94
CI = 81.06, 86.94
<span>Therefore at 95% confidence
level, the scores is from 81 to 87.</span>
Sorry what what is the question?
Answer:
The first angle is the smallest
Step-by-step explanation:
Step one:
given data
Angle 1= x+37
Angle 2= 90
angle 3= x+67
We know that the sum of angle in a triangle is 180
so
x+3+90+x+67= 180
collect like terms
2x+160= 180
2x=180-160
2x= 20
divide both sides by 2
x= 10
Step two:
so
Angle 1= 10+37= 47 °
Angle 2= 90= 90
angle 3= 10+67= 77 °
I’m not sure if this is correct but this is the way i would solve it.
first, make an equation with the given information
2x-3=30
Then, add three to both sides
2x=33
Finally, divide both sides by 2
x= 16.5
x represents the age of maggie so all you have to do is plug the solution into the equation to check your answer.
2(16.5)-3= 30