A coin is tossed six times. How many sequences of 3 heads and 3 tails are possible?How many sequences of 5 heads and 1 tails are possible?

Question

A coin is tossed six times. How many sequences of 3 heads and 3 tails are possible?How many sequences of 5 heads and 1 tails are possible?

Answer 1

This question can be answered by using nCr, which tells us how many combinations there are from n things, selected r at a time.  6C3 = 20; there are 20 different ways to get 3 heads & 3 tails in 6 tosses.

 

6C1 = 6; it's easy to see that there ar just 6 ways to get only one 'tails'--the tails coin can be first, 2nd, third,...6th & all the rest wluld be 'heads.'