Answer:
(a) Margin of error ( E) = $2,000 , n = 54
(b) Margin of error ( E) = $1,000 , n = 216
(c) Margin of error ( E) = $500 , n= 864
Step-by-step explanation:
Given -
Standard deviation 
= $7,500
= 1 - confidence interval = 1 - .95 = .05
= 
= 1.96
let sample size is n
(a) Margin of error ( E) = $2,000
Margin of error ( E) = 
E = 
Squaring both side
n = 54.0225
n = 54 ( approximately)
(b) Margin of error ( E) = $1,000
E =
1000 =
Squaring both side
n = 216
(c) Margin of error ( E) = $500
E =
500 =
Squaring both side
n = 864
There is no upper limit so, so x is greater than or equal to 24 (x ≥ 24)
Answer: -1/2 and 1/3
Step-by-step explanation:
Answer:
A. E(x) = 1/n×n(n+1)/2
B. E(x²) = 1/n
Step-by-step explanation:
The n candidates for a job have been ranked 1,2,3....n. Let x be the rank of a randomly selected candidate. Therefore, the PMF of X is given as
P(x) = {1/n, x = 1,2...n}
Therefore,
Expectation of X
E(x) = summation {xP(×)}
= summation {X×1/n}
= 1/n summation{x}
= 1/n×n(n+1)/2
= n+1/2
Thus, E(x) = 1/n×n(n+1)/2
Value of E(x²)
E(x²) = summation {x²P(×)}
= summation{x²×1/n}
= 1/n
Step-by-step explanation:
<h2>
Sum of two complementary angle is 90°</h2><h2 /><h2>
so. </h2><h2>
<R+<S =90°</h2><h2>
12x-3+7x-2=90°</h2><h2>
19x-5=90°</h2><h2>
19x=95°</h2><h2>
X= 5</h2>
<h2>
<R= 60-3=57°</h2>
