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
You multiply the numerator and denominator of 3/4 with 3 and multiply 1/3 with 4 on the bottom and top and after you get 36/144 you simplify it and you get 1/4 so thats your answer
I think it’s A?? Idk just my opinion I’m sorry if it’s wrong
Answer:
X=-6
Step-by-step explanation:
the sum of interior angels in a triangle is 180.
52+78=130
180-130=50
to get 56 to 50 x has to be negative
hope this helps :)
To add fractions, find the LCD - lowest common denominater, and then Combine. For LCD find where both bottom numbers equal the same so in this case you would have to multiply 9 times 11 and vice versa to equal 99. Once you do that the 5 thats on top of the 9 will also have to be multiplied by 11 and the 4 on top of the 11 will have to be multiplied by 9 so it could make sense. Now you must Combine - it would be 55/11 + 36/11. you only add the top numbers and leave the bottom number.(that is what its out of). Thus the answer is 91/11.
Answer is 99
