MHB What would the probability be for the 11th flip to be the same as 10th flip

  • Thread starter Thread starter xNICK1
  • Start date Start date
  • Tags Tags
    Probability
AI Thread Summary
The probability of the 11th flip being the same as the 10th flip of a fair coin is 1/2, as each flip is independent. If the coin is biased, the outcomes of the previous 10 flips can inform the probability, which in this case shows 6 heads and 4 tails. This results in an estimated probability of 0.6 for heads and 0.4 for tails on the 11th flip. The history of flips influences the likelihood of future outcomes, but does not alter the fundamental independence of each flip. Therefore, the probability can vary based on whether the coin is fair or weighted.
xNICK1
Messages
14
Reaction score
0
I'm wanting to know if there is a formula that can get the probability of then next flip, by taking the data/ averages of the last 10 flips.
So, if the last 10 flips were "H,T,T,H,H,T,T,H,H,H".
What would the probability be for the 11th flip to be the same as 10th flip?
 
Mathematics news on Phys.org
There are two possible outcomes for every toss so that probability would be 1/2. This is different than, say, "What is the probability of tossing two heads in a row?" which would be 1/2 * 1/2 = 1/4.
 
Assuming this is a fair coin, that the probability of "heads" or "tails" is always 1/2, then, pretty much by definition, the probability of heads or tails on the 11th flip is 1/2.

If we are not assuming that, but are considering the possibility that the coin is "weighted" so that one of "heads" or "tails" is more likely than the other, we could consider that "history", the first ten tosses, reflects which is more likely. Here the first ten tosses are "H,T,T,H,H,T,T,H,H,H", 6 heads, and 4 tails, then we would estimate the probability of heads on anyone toss, and in particular, the eleventh toss, is 0.6 and the probability of tails is 0.4.

Notice that, in this scenario, the fact that there are more heads than tails in the 10 tosses means that another head is more likely than another tail. Future tosses will \left(\right)not "make up" for previous tosses.
 
Thanks!
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
Thread 'Imaginary Pythagoras'
I posted this in the Lame Math thread, but it's got me thinking. Is there any validity to this? Or is it really just a mathematical trick? Naively, I see that i2 + plus 12 does equal zero2. But does this have a meaning? I know one can treat the imaginary number line as just another axis like the reals, but does that mean this does represent a triangle in the complex plane with a hypotenuse of length zero? Ibix offered a rendering of the diagram using what I assume is matrix* notation...
Fermat's Last Theorem has long been one of the most famous mathematical problems, and is now one of the most famous theorems. It simply states that the equation $$ a^n+b^n=c^n $$ has no solutions with positive integers if ##n>2.## It was named after Pierre de Fermat (1607-1665). The problem itself stems from the book Arithmetica by Diophantus of Alexandria. It gained popularity because Fermat noted in his copy "Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos, et...
Back
Top