Answer:
Z=-2
This value means that the score of Rachel 550 it's 2 deviations below the mean of the population
Step-by-step explanation:
1) Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
represent the population mean for the Graduate Record Exam (GRE)
represent the population standard deviation for Graduate Record Exam (GRE)
2) Solution to the problem
Let X the random variable that represent the Graduate Record Exam (GRE) of a population, and for this case we know the distribution for X is given by:
Where
and
We want to find the z score for a score of 550. And in order to do this we need to apply the formula for the z score given by:
If we apply this formula to our probability we got this:

So the answer for our case would be Z=-2
This value means that the score of Rachel 550 it's 2 deviations below the mean of the population
We have been given that :-
The length of a parasite in experiment A is 
The length of a parasite in experiment B is 
Let us write the the length of the parasite in experiment A in the exponent of -3.

Clearly, the length of parasite in experiment A is greater than the length of parasite in experiment B.
The difference in the length is given by


Therefore, the length of the parasite in experiment A is
inches greater than the length of the parasite in experiment B.
Answer:
2:30 pm
Step-by-step explanation:
In two hours (from 10am), she is 45 * 2 = 90 miles from vacation cabin.
From then on her average is still 45 mph and her husband's is 65 mph. So, husband catches her 20 miles (65-45=20) in every hour.
<em>The husband has to catch up 90 miles. How long would it take if he is catching up at 20 miles an hour?</em>
<em>90/20 = 4.5 hours</em>
<em />
<em>So husband starts at 10am and 4.5 hours form that time is 2.30pm</em>
Answer:
m=2
Step-by-step explanation:
slope is the average rate of change in a specific interval
we can calculate slope in this case with Δy/Δx or (y2-y1)/(x2-x1)
m=(y2-y1)/(x2-x1)
=(-1-7)/(-3-1)
=-8/-4
=2
Answer: 10.50 is what she has left to spend
Step-by-step explanation: Hope it helps!