Answer:
9/32 or 0.28125
Step-by-step explanation:
8 parents and 4 teachers
There are 12 possible outcomes.
probability = # of favorable outcomes / # of possible outcomes
Let's do the teachers first.
There are 4 teachers, and we are finding the probability for 3 of them being picked.
Therefore,
P = 3/4
Now let's do the parents.
There are 8 parents, and we want 3.
Therefore,
P = 3/8
Now, we do 
Therefore, the chance of 3 teachers and 3 parents being picked out of 4 teachers and 8 parents is 9/32, or in decimal form 0.28125.
Hope this helped!
part A)
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part B)
f(x) = 10 + 20x
so if you rent the bike for a few hours that is
1 hr.............................10 + 20(1)
2 hrs..........................10 + 20(2)
3 hrs..........................10 + 20(3)
so the cost is really some fixed 10 + 20 bucks per hour, usually the 10 bucks is for some paperwork fee, so you go to the bike shop, and they'd say, ok is 10 bucks to set up a membership and 20 bucks per hour for using it, thereabouts.
f(100) = 10 + 20(100) => f(100) = 2010.
f(100), the cost of renting the bike for 100 hours.
The distance between -3 and 0 is positive 3 , and the distance between 0 and 5 is 5, add 5 and 3 together to get a distance of 8
The answer for this one is x=17