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>
Answer:
1. x = 2
2. x = 21
Step-by-step explanation:
Hope this helps
Answer:
9 pieces
Step-by-step explanation:
28 inches rope cut into 3-inch pieces
There is no matching answer choice, if given numbers are correct then the answer is 9 full pieces
---------
<u>Note:</u>
- The close answer choice is 8
- 28/8 = 3 1/2 or 3.5
- So if cut into 3.5 inch pieces then it is 8 full pieces
- just in case it was typo 3 instead of 3.5
Answer:
x = 36/5
Step-by-step explanation:
Subtract 6 from both sides
x/3+6-2x-6 = -6-6
Simplify
x/3 - 2x = -12
Multiply both sides by 3
x/3 * 3 - 2x * 3 = -12 * 3
Simplify
-5x = -36
Divide both sides by -5
-5x/-5 = -36/-5
Simplify
x = 36/5
8.6
Since there is one number before the decimal, we don't have to move the decimal
8.6 * 10^0
Answer 8.6 * 10^0
