Assume that 25 probability students toss a fair coin 100 times each.What is the probability that at least one student gets exactly 50 heads?

Answer 1

The probability of exactly 50 heads in 100 tosses of a true coin is $\left(\genfrac{}{}{0ex}{}{100}{50}\right)$ * (1/2)^100; call this value p.

Then the probability that at least one of 25 students who do the tosses get exactly 50 heads is

1 - (1-p)^25