Answer:
d. 20
Step-by-step explanation:
Standard deviation is 4.5
Margin error for the problem is 2 hours
Probability 95%, that means that the siginficance level α is 1 – p
α = 1 – 0.95 = 0.05
margin of error (ME) can be defined as follows
ME = Z(α/2) * standard deviation/ √n
Where n is the sample size
Z(0.05/2) = Z(0.025)
Using a z table Z = 1.96
Now, replacing in the equation and find n
2 = 1.96 * 4.5/ √n
2 = 8.82/√n
√n = 8.82/2
√n = 4.41
n = 4.41^2
n = 19.44 ≈ 20
1•6 + 11•2
6+22
28 would be the answer
Answer:
This formula:
Cylinder Volume = π • r² • height
Volume = PI * 4 ^2 * 5
Volume = PI * 16 * 5
Volume = 251.327412 cubic inches
Step-by-step explanation:
Area=lw
l=2w
aera=2l^2
72=area
72=2l^2
divide both sides by 2
36=l^2
sqrt both sides
6=l
length=6 units
