Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

I remember now that I had 1/8 as the answer in my mind when i framed the question.........it only mentions about the first three heads......so essentially the last two throws are useless.....

the answer will always be 1/8 irrespective of the number of throws.......i wonder why i did not reply to stolyar's posting........or maybe i did thru a PM.

Say, if instead of 5 coins we had 1,241,352 coins. What is the p that first 3 coins will have heads? It is still 1/8, but i doubt you can calculate 2^1,241,352!

Best is to use 1/2^3. Three independent events.

I guess this is what brstorewala means when saying the answer is

hey....I got 1/8 too!!! [#permalink]
06 Jun 2003, 12:00

Well,Here is how I woked it out.....
P(getting a head)=1/2 so P(getting a head first three times)=1/2*1/2*1/2=1/8!!!!!!!Ofcourse.the p(of getting a tail )= 1/2 too.I am not sure about this logic!!!!

_________________

Its not about you getting knocked down,Its about how fast you get back up again!!!!