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
Start by proving to them that the number 0.57 can be converted into a fraction . A whole number can't exactly be put in to a fraction. 0.57 can be converted to 14.25/25. This information means that 0.57 IS a rational number. Hope this convinced them!
To know what to do first in a math problem we look to order of operations... PEMDAS stands for parentheses, exponents, multiplication, division, addition, and subtraction. So to begin we look for parentheses... do we have any? Why, yes, yes we do. Let's work!
(3+3) + 6 / 3 + 6 =
Add 3+3 in the parentheses. Since there is nothing else, the parentheses can go away.
6 + 6 / 3 + 6 =
Now, any exponents? Nope... Multiplication? Nope... division? Yes! Let's go!
6 + 2 + 6 =
Now all we have left is addition... Go for it!
8 + 6 = 14
Done!
Answer:
The conclusion to be drawn is:
The actual proportion of teenagers who do not smile is only 8%. It is clear that exactly 6 out of 10 teenagers will smile in their driver's license photo.
If we continued to take more samples of 10 teenagers, the center of the distribution would shift to
Step-by-step explanation:
Answer:
3 • (2xy - 7) • (xy + 2)
Step-by-step explanation:
(((2•3x2) • y2) - 9xy) - 42
6x2y2 - 9xy - 42 = 3 • (2x2y2 - 3xy - 14)