Answer:
P ( 5 < X < 10 ) = 1
Step-by-step explanation:
Given:-
- Sample size n = 49
- The sample mean u = 8.0 mins
- The sample standard deviation s = 1.3 mins
Find:-
Find the probability that the average time waiting in line for these customers is between 5 and 10 minutes.
Solution:-
- We will assume that the random variable follows a normal distribution with, then its given that the sample also exhibits normality. The population distribution can be expressed as:
X ~ N ( u , s /√n )
Where
s /√n = 1.3 / √49 = 0.2143
- The required probability is P ( 5 < X < 10 ) minutes. The standardized values are:
P ( 5 < X < 10 ) = P ( (5 - 8) / 0.2143 < Z < (10-8) / 0.2143 )
= P ( -14.93 < Z < 8.4 )
- Using standard Z-table we have:
P ( 5 < X < 10 ) = P ( -14.93 < Z < 8.4 ) = 1
6 miles as 31678 feet is 5 miles
<u>Solution-</u>
Fuel consumption rate = 40 miles per UK gallon (As the car is manufactured in UK)
1 UK gallon = 4.5459631 lit
1 US gallon = 3.7853060 lit


As the fuel consumption rate = 40 miles per gallon
⇒ You need 1 UK gallon of fuel to go 40 miles
⇒ You need 1.2009499 US gallon of fuel to go 40 miles
Or you can say that, to go 40 miles you need 1.2009499 US gallon of fuel
⇒ To go 1 mile you will need 
⇒ To go 738 miles you will need 0.0300237×738 = 22.1574906 US gallon of fuel
∴ 22.1574906 gallon of fuel is actually required.
∴ But, what she thinks will require is
(As she calculated using UK gallons)
Answer:
And if we solve for a we got
So the value of height that separates the bottom 20% of data from the top 80% is 23.432.
Step-by-step explanation:
Let X the random variable that represent the heights of a population, and for this case we know the distribution for X is given by:
Where
and
For this part we want to find a value a, such that we satisfy this condition:
(a)
(b)
As we can see on the figure attached the z value that satisfy the condition with 0.20 of the area on the left and 0.80 of the area on the right it's z=-0.842
If we use condition (b) from previous we have this:
But we know which value of z satisfy the previous equation so then we can do this:
And if we solve for a we got
So the value of height that separates the bottom 20% of data from the top 80% is 23.432.
Answer:
I believe that it is 2, I'm not 100% but ill take the guess
Step-by-step explanation: