Answer:
37.23% probability that randomly selected homework will require between 8 and 12 minutes to grade
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
What is the probability that randomly selected homework will require between 8 and 12 minutes to grade?
This is the pvalue of Z when X = 12 subtracted by the pvalue of Z when X = 8. So
X = 12
has a pvalue of 0.4052
X = 8
has a pvalue of 0.0329
0.4052 - 0.0329 = 0.3723
37.23% probability that randomly selected homework will require between 8 and 12 minutes to grade
The answer is C. Remember that the equation for point slope form is y-y1=m(x-x1). In this one they give you x1, y1, and m which is your slope... the slope is -12 so m=-12. (x1,y1) is (5,3) so x1=5 and y1=3. Plugging all of these in you get y-3=-12(x-5) so your answer is C
All 4 sides of a square are of the same length.
The formula for the area of a square is s*s = area where s is the length of one side of the square.
s^2 = 81
s = 9 or -9
-9 does not apply here but 9 does.
Each side of the square deck is 9 feet long.
There are 60 min per hour.
There are 24 hours in one day, so there are 60 times 24= 1,440 minutes in a day.
Person A: for 45 minutes per day had a heart rate of 150, and for 1,395 minutes per day had a heart rate of 60.
This means that her heart rate totaled (45x150) + (1,395x60) = 90,450 beats per day.
Person B: for 1,440 minutes per day had a heart rate of 72 beats per minute.
This means that her heart rate totaled (1,440x72) = 103,680 beats per day.
So for 365 days: 365(103,680-90,450)= 4,828,950-this is the number of beats MORE per year of Person B than Person A.
