What is the probability of flipping a fair coin three times and the co

Question

What is the probability of flipping a fair coin three times and the coin landing on heads on exactly one flip?

A. 1/8
B. 1/4
C. 3/8
D. 1/2
E. 3/4

vitaliyGMAT · Answer

H T T  =  P(H)*P(T)*P(T)*# of arrangements  =  \frac{1}{2}*\frac{1}{2}*\frac{1}{2} * \frac{3!}{1!*2!} = \frac{3}{8}

Answer C.

shashankism · Answer

No. of possible outcome of flipping of Coin = 2*2*2 = 8 (Each flip can be either H or T)
No. of events in which there will be H in exactly one flip = HTT, THT, TTH = 3

So, probability = 3/8

Answer C

IanStewart · Answer

I'd probably solve this as others did above (because those solutions generalize more easily to situations with more coinflips) but another way: the probability of getting three heads is (1/2)^3 = 1/8. That equals the probability of getting three tails. The rest of the time, or 6/8 of the time, we either get one head or we get one tail. Those outcomes are equally likely, so we get one head 3/8 of the time.

BrushMyQuant · Answer

What is the probability of flipping a fair coin three times and the coin landing on heads on exactly one flip?

Coin is tossed 3 times => Total number of cases =  2^3  = 8

To find the cases in which the coin lands on exactly one flip we need to select one place out of three _ _ _ in which we will get Heads.

We can put Head in any of those 3 places in 3 ways.

=> P(1H) =  \frac{3}{8}

So,  Answer will be C 
Hope it helps!

Watch the following video to learn How to Solve Probability with Coin Toss Problems

https://www.youtube.com/watch?v=LRURv38kZw8

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