Answer:
0.194
Step-by-step explanation:
Probability that BOTH are democrats means probability of <u>"one being democrat"</u> AND <u>"another also being democrat"</u>.
The AND means we need to MULTIPLY the individual probability of a person being democrat.
Probability that a voter is democrat is 44% (0.44) -- stated in the problem
Now, Probability BOTH being Democrats is simply MULTIPLYING 0.44 with 0.44
Rounded to nearest thousandth, 0.194
Last answer choice is correct.
a) You are told the function is quadratic, so you can write cost (c) in terms of speed (s) as
... c = k·s² + m·s + n
Filling in the given values gives three equations in k, m, and n.
Subtracting each equation from the one after gives
Subtracting the first of these equations from the second gives
Using the next previous equation, we can find m.
Then from the first equation
[tex]28=100\cdot 0.01+10\cdot (-1)+n\\\\n=37[tex]
There are a variety of other ways the equation can be found or the system of equations solved. Any way you do it, you should end with
... c = 0.01s² - s + 37
b) At 150 kph, the cost is predicted to be
... c = 0.01·150² -150 +37 = 112 . . . cents/km
c) The graph shows you need to maintain speed between 40 and 60 kph to keep cost at or below 13 cents/km.
d) The graph has a minimum at 12 cents per km. This model predicts it is not possible to spend only 10 cents per km.
