Answer:
The standard error of the sample mean is _17.677_ psi.
Step-by-step explanation:
<u>Explanation</u>:-
A random sample of n = 8 specimens is collected.
Given sample size is n = 8
Given mean of the population 'μ' = 2500 psi
standard deviation 'σ' = 50 psi
Let x⁻ is the mean of the observed sample
Standard error of the sample mean =
...(i)
Given Population of standard error (S.D) 'σ' = 50 psi
Now substitute all values in (i)

<u>Conclusion</u>:-
The standard error of the sample mean is _17.677psi.
50,5-100%
40,4-х%
x=(40,4*100)\50,5=80%
Answer:80%
From points A and B, the distance between which is 1020 mi
The speed of one train was 10 mph greater than the speed of the other one
Let the Speed of first train is x
Speed of second train is x+ 10
Time = 5 hours
Distance = speed * time
Distance traveled by first train = x * 5= 5x
Distance traveled by second train = (x+10) * 5= 5x + 50
the trains had not met yet and were 170 mi apart.
the distance between A and B is 1020 mi, Distance traveled by two trains = 1020 - 170 = 850 miles
Distance traveled by first train + second train = 850
5x + 5x + 50 = 850
10x + 50 = 850
Subtract both sides by 50
10x = 800
x= 80
Speed of first train is 80 miles per hour
Speed of second train is 90 miles per hour