A fair coin is tossed 20 times. Let X be the number of heads thrown in the first 10 tosses, and let Y be the number of heads tossed in the last 10 tosses. Find the conditional probability that X = 6, given that X + Y = 10.
X and Y are independent as outcome in first 10 tosses are independent of the outcome in last 10 tosses.
Y ~ Binomial( n = 10, p = 0.5)
The probability mass function of Y is
Now,
since X and Y are independent
(ans)
A fair coin is tossed 20 times. Let X be the number of heads thrown in...
A fair coin is tossed 20 times. Let X be the number of heads thrown in the first 10 tosses, and let Y be the number of heads tossed in the last 10 tosses. Find the conditional probability that X = 6, given that X + Y = 10.
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