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
Answer:
Step-by-step explanation:
if the item is 430, and the sales tax is 25.80
we can find how much is 1%
430/100=4.30
25.80/4.30=6
the sales tax is 6%
Answer: 
Explanation:
Highlight the first digit on the very left (2). The 7 right next to it means we'll round that 2 up to a 3. Every other digit becomes a zero.
The number 27,895,168,401,112 rounds to 30,000,000,000,000 which is the number 30 trillion.
It converts to the scientific notation
because we basically start with 3.0 and move the decimal point 13 spots to the right to arrive at 30 trillion as shown above.
Answer: 500m
Explanation:
If the scale of the drawing is 1:500 then the real playground should be 500:1 which is 500m
Largest to Smallest:-
First lets write all the numbers down. 45, 94, 85, 490, 85, 93, 85, 035, 85.
035 is 35.
So lets order them now.
The biggest number is 490 and smallest is 35 (035).
490 - 94 - 93 - 85 - 85 - 85 - 85 - 035 (35)