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:
Step-by-step explanation:
Using the parallelogram theorem
3x-8 = 10x+13
-7x = 21
x = -3
Substitute
3(-3) - 8
-17
10(-3) + 13
-17
Answer:
8710 units
Step-by-step explanation:
<em>Step 1: Write all the data</em>
Fixed cost: $9000
Average variable cost: 9.3 per unit
Total cost: 90,000
Total units: x
<em>Step 2: Find the total variable cost</em>
Average variable cost is per unit so it has to be multiplied by the number of units to find the total variable cost.
Total variable cost = average variable cost per unit x number of units
Total variable cost = 9.3x
<em>Step 3: Make the formula for finding x</em>
Total cost = total fixed cost + total variable cost
90,000 = 9000 + 9.3x
81000 = 9.3x
x = 8709.67
Rounded off to 8710 units
!!
Answer:
no
Step-by-step explanation:
541982/3 = 180,660.667