V = PI x r^2 x H
1348.79 = 3.14 x 5.5^2 x H
1348.79 = 94.985 x h
h = 1348.79 / 94.985
h = 14.2 cm ( round answer if needed)
Using the formula <span>Z = (X - μ) / σ, X being 900, </span>μ being 1100, and <span> σ being 100, we can get the Z-score of -2.</span>
40/50=0.8
0.8*100=80%
Hope this helps!
Answer:
Explained below.
Step-by-step explanation:
The human resource department at a certain company wants to conduct a survey regarding worker morale. The department has an alphabetical list of all 4,502 employees at the company and wants to conduct a systematic sample of size 50.
Systematic sampling is a kind of probability sampling method in which individuals from a larger population are nominated according to a random initial point and a static, periodic interval.
(a)
A sample of size 50.
Then the value of <em>k</em> will be: 
Thus, the value of <em>k</em> is 90.
(b)
Label the employees from 1 to 4502.
And select every 90th employee.
So, the individuals who will be administered the survey are:
90th, 180th, 270th,...
I can’t understand why everyone complicates this question. It can be easily solved by similar triangles.
In this png, we have something to make sure.
∠B=∠DAB
∠
B
=
∠
D
A
B
(Yes, dab)
This also means AD=BD
A
D
=
B
D
.
This is our basic construction of D, which is going to help us.
∠ADC=∠DAB+∠B=2∠B=∠CAB
∠
A
D
C
=
∠
D
A
B
+
∠
B
=
2
∠
B
=
∠
C
A
B
∠CAD=∠CAB−∠DAB=∠B
∠
C
A
D
=
∠
C
A
B
−
∠
D
A
B
=
∠
B
These are based on the fact that ∠A=2×∠B
∠
A
=
2
×
∠
B
Actually these conditions suffice. Because I am just proving that △ACD∼△BCA
△
A
C
D
∼
△
B
C
A
Similarity makes us realize the following:
ACBC=ADAB
A
C
B
C
=
A
D
A
B
and
ACBC=CDAC
A
C
B
C
=
C
D
A
C
So
AC×AB=BC×AD
A
C
×
A
B
=
B
C
×
A
D
and
AC2=BC×CD
A
C
2
=
B
C
×
C
D
So
BC2=BC×(BD+CD)=BC×(AD+CD)
B
C
2
=
B
C
×
(
B
D
+
C
D
)
=
B
C
×
(
A
D
+
C
D
)
=AC×AB+AC2
=
A
C
×
A
B
+
A
C
2
Q.E.D.
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