Final Study Guide MA 123
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1)
There are 25 people in a research study. If you choose one to receive Drug A, one to
receive Drug B, and one to receive the placebo, how many ways are there to make
your choices?
2)
You coach your child’s soccer team. Of the nine children on the bench, you plan to
send two to go get the drinks from the car. How many ways are there to make your
choice?
3)
You are on a committee to choose four new lifeguards for the city pool. If you
choose four from the 50 people who apply, how many ways are there to choose who
to hire?
4)
You are selling notebook computers. If your buyers can choose with or without a
wireless card, with or without a second battery, either a 256M, 512M or 1 G memory,
and their option of 30, 40 or 80 G hard drive, how many ways can they configure
their computer?
5)
There are 12 men and 8 women in your club. You are going to choose a President,
Vice President and Treasurer.
a)
a. How many ways are there to choose these three people?
b)
How many ways are there to have all the positions filled by men?
c)
What is the probability that the three people are all men?
6)
The table below shows the number of people who play each instrument where you
work (assume these represent distinct people – that a drummer does not also play
guitar). If someone gets fired at work, what is the probability that you are losing a
trumpet player?
Instrument # players
Guitar 8
Keyboard 12
Drums 6
Trumpet 7
7)
You have 30 samples of hamburger from a grocery store with questionable sanitation
standards. One of them is tainted with E. coli. Four will be tested.
a)
How many ways are there to select which to test?
b)
What is the probability that the tainted package is tested?
