Question

In: Statistics and Probability

Suppose we have a biased coin that comes up heads 55% of the time. We perform...

  1. Suppose we have a biased coin that comes up heads 55% of the time. We perform an experiment where we toss the coin until the first tails appears. Let T be the number of tosses until the first tails. What is the expected value and standard deviation for T? What is the probability that it takes 5 or more tosses before the first tails appears?

Solutions

Expert Solution

suppose we have series of independent trials or repetetion and in each trial the probability of succes p=0.45 (=1-q=1-55%=0.45)i.e probability of obtaining tails. then the probability that there are t failures (obtaining heads is taken as failure with probability q=55%=0.55) preceeding first success is given by (q^t)p

this is nothing but the geometric distribution so, we will use geometric distribution p.m.f q^t p ,q=1-p

=0.0.05033(approx.)


Related Solutions

A magic shop sells a coin which is rather biased. It comes up heads 40% of...
A magic shop sells a coin which is rather biased. It comes up heads 40% of the time. Suppose the shop owner puts on a demonstration his customers by flipping the coin 12 times. For each item below, write the letter which corresponds to the correct value. Some letters may not be used and some letters may be used more than once. • Probability of exactly 6 heads? • Probability of exactly 9 tails? • Probability of more than than...
Flip a coin 10 times. Put a 1 each time the coin comes up heads and...
Flip a coin 10 times. Put a 1 each time the coin comes up heads and a 0 each time the coin comes up tails. Count the number of heads you obtained and divide by 10. What number did you get? a. Is the number you obtained in part (a) a parameter or a statistic? b. Now flip the coin 25 times. Put a 1 each time you obtain a heads and a 0 for tails. Count the number of...
1. Amy tosses 12 biased coins. Each coin comes up heads with probability 0.2. What is...
1. Amy tosses 12 biased coins. Each coin comes up heads with probability 0.2. What is the probability that fewer than 3 of the coins come up heads? Answer: 0.5583 2. Amy shoots 27000 arrows at a target. Each arrow hits the target (independently) with probability 0.2. What is the probability that at most 2 of the first 15 arrows hit the target? Answer: 0.398 3. Amy tosses 19 biased coins. Each coin comes up heads with probability 0.1. What...
) Suppose you flip a coin. If it comes up heads, you win $20; if it...
) Suppose you flip a coin. If it comes up heads, you win $20; if it comes up tails, you lose $20. a) Compute the expected value and variance of this lottery. b) Now consider a modification of this lottery: You flip two fair coins. If both coins come up heads, you win $20. If one coin comes up heads and the other comes up tails, you neither win nor lose – your payoff is $0. If both coins come...
Coin 1 comes up heads with probability 0.6 and coin 2 with probability 0.5. A coin...
Coin 1 comes up heads with probability 0.6 and coin 2 with probability 0.5. A coin is continually flipped until it comes up tails, at which time that coin is put aside and we start flipping the other one. (a) What proportion of flips use coin 1? (b) If we start the process with coin 1 what is the probability that coin 2 is used on the fifth flip? (c) What proportion of flips land heads?
Suppose you flip a biased coin (that lands heads with probability p) until 2 heads appear....
Suppose you flip a biased coin (that lands heads with probability p) until 2 heads appear. Let X be the number of flips needed for this two happen. Let Y be the number of flips needed for the first head to appear. Find a general expression for the condition probability mass function pY |X(i|n) when n ≥ 2. Interpret your answer, i.e., if the number of flips required for 2 heads to appear is n, what can you say about...
In a sequence of independent flips of a fair coin thwr comes up heads with probability...
In a sequence of independent flips of a fair coin thwr comes up heads with probability 0.6, what is the probability that there is a run of three consecutive heads within the first 10 flips? Show a Markov chain that counts the number of consecutive heads attained.
Please give detailed solution for this Coin 1 comes up heads with probability .3, whereas coin...
Please give detailed solution for this Coin 1 comes up heads with probability .3, whereas coin 2 comes up heads with probability .6. A coin is randomly chosen and flipped 10 times. (a) Find the probability the first flip lands heads. (b) Find the expected number of heads in the 10 flips. (c) Find the probability that there are a total of 7 heads.
Suppose that we flip a fair coin until either it comes up tails twice or we...
Suppose that we flip a fair coin until either it comes up tails twice or we have flipped it six times. What is the expected number of times we flip the coin?
You toss a biased coin with the probability of heads as p. (a) What is the...
You toss a biased coin with the probability of heads as p. (a) What is the expected number of tosses required until you obtain two consecutive heads ? (b) Compute the value in part (a) for p = 1/2 and p = 1/4.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT