Answer:
5/5
Step-by-step explanation:
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:
x = 16
Step-by-step explanation:
(5x + 12)° + (6x - 8)° = 180°
(5x + 12 + 6x - 8)° = 180°
(11x + 4)° = 180°
11x + 4 = 180
11x = 180- 4
11x = 176
x = 176/11
x = 16
Answer:
There are 650 cannonballs
Step-by-step explanation:
If you look closely in the picture, you can see that:
- 1st row has 1 ball
- 2nd row has 4 balls
- 3rd row has 9 balls
- 4th row has 16 balls
etc. etc.
We can see that the number of balls is the square of the row number. There are a total of 12 rows. So, rest of the rows has:
- 5th row has 25 balls
- 6th row has 36 balls
- 7th row has 49 balls
- 8th row has 64 balls
- 9th row has 81 balls
- 10th row has 100 balls
- 11th row has 121 balls
- 12th row has 144 balls
If we add up all those, we get total number of balls:

There are 650 cannonballs