Question

What is the probability of throwing one dice seven times in a row and getting the number 6 fallen exactly 3 times?

Answer 1

$\bf\large\underline\red{Solution:-}$

There are 2 such possible outcomes after each throw and 2^7 = 128 possible outcomes after 7 throws. Those with a 6 showing up 3 times and no 6 turning up 4 times = 7!/(4!)( 3!) = 35.