Answer:
a. The expected or average costs for all weekly rat purchases is $20.00
Step-by-step explanation:
a. A mean value of $20.00 means that over a period of 52 weeks, the company can expect to spend $20.00 per week on rat purchases.
b. This is incorrect since individual values don't interfere in the mean. For instance, if half the weeks had a cost of $19.00 and the other half had a cost of $21.00, the mean cost would still be $20.00 even though no particular week had a $20.00 cost
c. Incorrect. The median is the central value in a distribution; the median and the mean are not necessarily the same.
d. Incorrect, same as item b.
Memorize the definition of standard deviation: the sd is the square root of the average of the squared deviations of the mean. Wow. Let's do it.
Step 1. First we need the mean. That's easy. Add them up and divide by the count. Check if you get 16.88/5 = 2.81333.
Step 2. Now we're going to subtract this from each of the values, and square the result. Don't worry about negative signs, the squaring will get rid of those. Example for the first number:
(1 - 2.813)^2 = 3.29
The list of numbers I get is (rounded, in reality round as little as possible):
3.29, 2.60, 1.41, 2.35, 1.66, 6.18
Step 3: Add them all up. I get 17.49.
Step 4: Divide by the count of numbers. 17.49/6 = 2.91
Step 5: Take the square root from this result. SQRT(2.91) = 1.707305
TIP: Use excel to do all these steps, then run the set of numbers through Excel's built-in sd function (called STDEV.P) and see that you get the same result!
Well, since we know 30 is the unit rate of determining the weight of someone, in order to find the approximate number of quarters of blood in the person's body, all we'll have to do is divide the amount of pounds the person is divided by 30 to figure out the approximate number of quarters of blood in the person's body.So we'll do 120 divided by 30, which is 4.So there are 4 quarters of blood in the 120 pound person.
Good luck with your studies, I hope this helps~!
Answer:
r = - 11
Step-by-step explanation:
Calculate the slope m using the slope formula and equate to - 4
m =
with (x₁, y₁ ) = (4, 5) and (x₂, y₂ ) = (8, r)
m = = = - 4 ( multiply both sides by 4 )
r - 5 = - 16 ( add 5 to both sides )
r = - 11