answersLogoWhite

0


Best Answer

If you know that two of the four are already heads, then all you need to find is

the probability of exactly one heads in the last two flips.

Number of possible outcomes of one flip of one coin = 2

Number of possible outcomes in two flips = 4

Number of the four outcomes that include a single heads = 2.

Probability of a single heads in the last two flips = 2/4 = 50%.

User Avatar

Wiki User

10y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: What is the probability of exactly three heads in four flips of a coin given at least two are heads?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Related questions

What is the probability of obtaining exactly seven heads in eight flips of a coin given that at least one is a head?

The probability of obtaining 7 heads in eight flips of a coin is:P(7H) = 8(1/2)8 = 0.03125 = 3.1%


What is the probability of obtaining exactly four heads in five flips of a coin given that at least three are heads?

We can simplify the question by putting it this way: what is the probability that exactly one out of two coin flips is a head? Our options are HH, HT, TH, TT. Two of these four have exactly one head. So 2/4=.5 is the answer.


What is the probability of obtaining exactly six heads in seven flips of a coin given that at least one is a head?

The requirement that one coin is a head is superfluous and does not matter. The simplified question is "what is the probability of obtaining exactly six heads in seven flips of a coin?"... There are 128 permutations (27) of seven coins, or seven flips of one coin. Of these, there are seven permutations where there are exactly six heads, i.e. where there is only one tail. The probability, then, of tossing six heads in seven coin tosses is 7 in 128, or 0.0546875.


What is the probability of obtaining exactly 5 heads in 6 flips of a fair coin?

It is approx 0.0938


What is the probability of obtaining exactly two heads in three flips of a coin given that at least one is a head?

The probability of obtaining exactly two heads in three flips of a coin is 0.5x0.5x0.5 (for the probabilities) x3 (for the number of ways it could happen). This is 0.375. However, we are told that at least one is a head, so the probability that we got 3 tails was impossible. This probability is 0.53 or 0.125. To deduct this we need to divide the probability we have by 1-0.125 0.375/(1-0.125) = approximately 0.4286


You toss 3 coins What is the probability that you get exactly 2 heads given that you get at least one head?

you toss 3 coins what is the probability that you get exactly 2 heads given that you get at least one head?


What is the probability of obtaining exactly three heads in four flips of a coin given that at least two are heads?

Pr(3H given >= 2H) = Pr(3H and >= 2H)/Pr(>=2H) = Pr(3H)/Pr(>=2H) = (1/4)/(11/16) = 4/11.


What is the probability of obtaining exactly six heads in seven flips of a coin?

7*(1/2)7 = 7/128 = 5.47% approx.


What is the probability that in four coin flips you get at least 2 heads?

50%


What are the odds against getting exactly two heads in three successive flips of a coin?

Three in eight are the odds of getting exactly two heads in three coin flips. There are eight ways the three flips can end up, and you can get two heads and a tail, a head and a tail and a head, or a tail and two heads to get exactly two heads.


What is the probability of 3 heads and 2 tails on five flips of a coin?

It is 0.3125


What is the probability of obtaining exactly five heads in six flips of a coin given that at least one is a head?

The probability that you will toss five heads in six coin tosses given that at least one is a head is the same as the probability of tossing four heads in five coin tosses1. There are 32 permutations of five coins. Five of them have four heads2. This is a probability of 5 in 32, or 0.15625. ----------------------------------------------------------------------------------- 1Simplify the problem. It asked about five heads but said that at least one was a head. That is redundant, and can be ignored. 2This problem was solved by simple inspection. If there are four heads in five coins, this means that there is one tail in five coins. That fact simplifies the calculation to five permutations exactly.