When six fairs coins are tossed simultaneously, in how many of the outcomes will at most three of the coins turn up as heads ?

When six fairs coins are tossed simultaneously, in how many of the outcomes will at most three of the coins turn up as heads ? Correct Answer 42

The question requires you to find number of the outcomes in which at most 3 coins turn up as heads.i.e., 0 coins turn heads or 1 coin turns head or 2 coins turn heads or 3 coins turn heads.

 

The number of outcomes in which 0 coins turn heads is 6C0=1 

The number of outcomes in which 1 coin turns head is =6C1=6 

The number of outcomes in which 2 coins turn heads is6C2=15 

The number of outcomes in which 3 coins turn heads is6C3=20

 

Therefore, total number of outcomes =1+6+15+20= 42 outcomes

Related Questions

The question below is followed by two statements I and II. You have to determine whether the data given is sufficient for answering the question. You should use the data and your knowledge of mathematics to choose the best possible answer.  Belly has some coins out of which some are of 25 Cent and Some are of 50 Cent. If he has a total of 250 coins, how many coins does he have of 25 Cent? I) Belly has three times as many as 50 Cent coins as 25 Cent coins. II) Belly has 20 more 25 cent coins than the 50 Cent coin.