Answer:
She ran 5 laps
Step-by-step explanation:
Why? Because with each lap stating to be one and a half miles; you first and only step is to divide, seeing how each time you put 1 1/2 into the value of this 7 1/2 miles, you got a lap each time.
you divide 7 1/2 by 1 1/2,
this results in getting, 5
15/2 if you are binging it to simplest form
Answer:
45 Handshakes
Step-by-step explanation:
45 Handshakes have taken place all together
Answer:
a) 
And replacing we got:

b) 
And replacing we got:

c) 
And replacing we got:

Step-by-step explanation:
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".
Part a
Let X the random variable of interest for this case. We define the z score with the following formula:
And for this case we know that 
If we solve for x from the z score formula we got:

And replacing we got:

Part b
Let X the random variable of interest for this case. We define the z score with the following formula:
And for this case we know that 
If we solve for x from the z score formula we got:

And replacing we got:

Part c
Let X the random variable of interest for this case. We define the z score with the following formula:
And for this case we know that 
If we solve for x from the z score formula we got:

And replacing we got:

The minimum happens at x = -b/2a
x = -30 / 2(3) = -30/6 = -5
Now replace x in the equation with -5 and solve:
3(-5)^2 + 30(-5) +27 = 75 - 150 + 27 = -48
The minimum is at (-5,-48)