You have to calculate how many ways you can select six things (r)
from a set of 9 things (n). (See attached formula).
9! / 6! * (3!) =
9*8*7 * 6! / 6! * 3! =
9*8*7 / 3! =
3 * 4 * 7 = 84 lineups
Answer:
see below
Step-by-step explanation:
Put -1 where x is in each expression and evaluate it.
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You will find that the expression is zero when the numerator is zero. And you will find the numerator is zero when it has a factor that is equivalent to ...
(x +1)
Substituting x=-1 into this factor makes it be ...
(-1 +1) = 0
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Evaluating the first expression, we have ...

This first expression is one you want to "check."
You can see that the reason the expression is zero is that x+1 has a sum of zero. You can look for that same sum in the other expressions. (The tricky one is the one with the factor (x -(-1)). You know, of course, that -(-1) = +1.)
Answer:
The answer for standard deviation would be:
4.382
120/2 = x/5....120 miles to 2 hrs = x miles to 5 hrs
cross multiply
(2)(x) = (120)(5)
2x = 600
x = 600/2
x = 300....the motorcyclist would travel 300 miles in 5 hrs
or u could do it this way..
120/2 = 60 miles per hr
60 * 5 = 300 miles