How to solve this Probability problem?

[user4632]

Hello everyone,

In this problem, if we use simple concept of probability that two event occur simultaneously then the answer would be 1/6 * 1/6 = 1/36.

But what i have been thinking is, that probability value is for raining on any two days which may be monday and Saturday or sunday and monday. How can we ensure that probability is exactly for event happening on monday and tuesday.

The answer given on book is also 1/36. Is it correct?

[Leaderboard]

You can use symmetry here; every day is the same.

[user4632]

Hi, i couldnot get what you are trying to explain. Can you please explain?

[Leaderboard]

You said

@user4632

But what i have been thinking is, that probability value is for raining on any two days which may be monday and Saturday or sunday and monday. How can we ensure that probability is exactly for event happening on monday and tuesday.

The answer is that it doesn’t matter. You could have the question ask for Monday and Tuesday, or Tuesday and Thursday, or any of the \binom{7}{2} combinations. The answer is always the same - that’s the symmetry I was referring to.