Answer:
Step-by-step explanation:
We would use the t- distribution.
From the information given,
Mean, μ = 2950
Standard deviation, σ = 115
number of sample, n = 25
Degree of freedom, (df) = 25 - 1 = 24
Alpha level,α = (1 - confidence level)/2
α = (1 - 0.98)/2 = 0.01
We will look at the t distribution table for values corresponding to (df) = 24 and α = 0.01
The corresponding z score is 2.492
We will apply the formula
Confidence interval
= mean ± z ×standard deviation/√n
It becomes
2950 ± 2.492 × 115/√25
= 2950 ± 2.492 × 23
= 2950 ± 57.316
The lower end of the confidence interval is 2950 - 57.316 =2892.68
The upper end of the confidence interval is 2950 + 57.316 = 3007.32
The solution is correct.
Answer:
6
Step-by-step explanation:
Area of decagon is given by:
Area=1/2(nsr)
where:
n=number of sides
s=side length
r=height
thus the area will be given by:
Area=1/2(10*4*6.2)
Area=124 cm^2
Answer:
The dimension of box=
Step-by-step explanation:
We are given that
Volume of box=4 cubic feet
Let x be the side of square base and h be the height of box
Volume of box=
Now, surface area of box,A=
Substitute x=2
Hence, the area of box is minimum at x=2
Therefore, side of square base,x=2 ft
Height of box,h=
Hence, the dimension of box=
Answer:
y + x = 7
Step-by-step explanation:
Standard form should be
y - 9 = -(x+2)
y = -x -2 +9
y + x = 7
