Permutation and Combination

There's probably a really good mathsy way to do it. Common sense tells me this, though:


I would just bodge it by finding the total amount of 4-number combinations.

And then there's a 50% probability that the first number is a 3 or a 4 making the number >3000.


So divide that total by 2 and you're there.


@TeeEm for a better answer.

will do this tomorrow

okay thanks, they you explain it to me please!

I got 66

Ain't the answer mate!
The answer is 102, but i don't know how to do that!!

Can you give your workings?

sorry yes 102
tiny number error

Can you explain it to me??

I am off to my morning walk now
After my walk I can.

That is one of a long walk!

Q24 on http://www.madasmaths.com/archive/maths_booklets/statistics/combinations_and_permutations.pdf

thank you!