0
$\begingroup$

I am trying to count the number of ways to play 4 indistinguishable objects in 6 bins. Each bin can contain either 0 or 1 object. We can think of this as the number of binary strings of length 6 with exactly four 1's. Thanks!

$\endgroup$
  • 2
    $\begingroup$ Welcome to Math SE. What else have you tried so far and are having difficulty with? $\endgroup$ – John Omielan Dec 23 '18 at 1:02
  • 5
    $\begingroup$ Approaching the problem through binary strings is a good idea. The numbers are sufficiently small that you should be able to list all the possibilities, from which you could then derive a formula. $\endgroup$ – N. F. Taussig Dec 23 '18 at 1:03
2
$\begingroup$

Let me draw you 6 bins:

|_|_|_|_|_|_|

now let me give you an example:

|x|x|x|_|x|_|

and another example:

|x|_|x|_|x|x|

and another example

|x|_|_|x|x|x|

in how many ways can you put those x in 6 bins?

Let me sharpen the question: in how many ways can you choose 4 items from 6? and here's another nice thing to notice...in how many ways can you choose 2 from 6? (hint: same answer)

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.