Question 821295: 1. If five cards are drawn at random from a standard 52 card pack of cards, what is the chance that:
(a) all cards are the same colour (either all black or all red) ?
(b) at least one of the cards is a three?
(c) exactly one of the cards is a three?
2. If three standard dice are rolled, what is the chance that their sum is divisible by three?
3. Suppose that on a building site there is a probability of an accident of .2% every day. What is the chance that there is no accident in one year?
4. If a fair coin is tossed 100 times and each time a head comes up, what is the chance that the next toss is a tails?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! 1. If five cards are drawn at random from a standard 52 card pack of cards, what is the chance that:
(a) all cards are the same colour (either all black or all red) ?
Pick a color:: 2 ways
Select 5 cards of that color:: 26C5
Ans: 2*(26C5)/52C5
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(b) at least one of the cards is a three?
Ans:: 1 - P(none is three) = 1 - [48C5/52C5]
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(c) exactly one of the cards is a three?
Ans: 4C1*48C4/52C5
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2. If three standard dice are rolled, what is the chance that their sum is divisible by three?
List all the sums; Count the ones that are divisible by 3; Divide
that number by 6^3 to get the probability
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3. Suppose that on a building site there is a probability of an accident of .2% every day. What is the chance that there is no accident in one year?
Ans: Use a Bernouli method to solve
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4. If a fair coin is tossed 100 times and each time a head comes up, what is the chance that the next toss is a tails?
Ans: 1/2 because the result of each toss is an independent event.
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Cheers,
Stan H.
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