Answer:
(53.812 ; 58.188) ; 156
Step-by-step explanation:
Given that :
Sample size (n) = 51
Mean (m) = 56
Standard deviation (σ) = 9.5
α = 90%
Using the relation :
Confidence interval = mean ± Error
Error = Zcritical * (standard deviation / sqrt (n))
Zcritical at 90% = 1.645
Error = 1.645 * (9.5 / sqrt(51))
Error = 1.645 * 1.3302660
Error = 2.1882877
Hence,
Confidence interval :
Lower boundary = 56 - 2.1882877 = 53.8117123
Upper boundary = 56 + 2.1882877 = 58.1882877
Confidence interval = (53.812 ; 58.188)
2.)
Margin of Error (ME) = 1.25
α = 90%
Sample size = ((Zcritical * σ) / ME)^2
Zcritical at 90% = 1.645
Sample size = ((1.645 * 9.5) / 1.25)^2
Sample size = (15.6275 / 1.25)^2
Sample size = 12.502^2 = 156.3000
Sample size = 156
Answer:
B.
Step-by-step explanation:
Answer:
120-x
Step-by-step explanation:
If x is already less, then you don't need absolute value
Answer:
y = 2
Step-by-step explanation:
varies inversely
xy = k
y = 7 when x = 2/3
(2/3)7 = k
14/3 = k
k = 14/3
--------------------
find y when x = 7/3
(7/3)y = 14/3
multiply both sides by 3/7
y = 14/3 * 3/7
y = 2
Answer: 339.29ft^3
Step-by-step explanation:
The formula for a cylinder is πr^2h
In your scenario, r=8 and h=3 so put those into the equation -
π8^2(3) and just solve!
