View Full Version : Simple probability question

10-14-2005, 06:31 PM
I assume this is a simple problem to solve for someone who isn't as dumb as I am. Appreciate it if anyone could take the time.

What are the odds of an event with a 1/30 chance of failure failing to occur 6 times in a row? (For example, starting my car. If starting my car has a success rate of 29/30, what are the chances of it failing to ignite 6 times in succession?)

Is there a general method for solving this problem?

Ty in advance.

10-14-2005, 06:34 PM
Yep, this is simple if each trial is independent (i.e. the fact that the last one failed does not affect the probability that the next will fail).

Just multiply the probabilities together. So, in your example...

P(6 failures in a row) = (1/30) * (1/30) * (1/30)...
= (1/30)^6