Gallery
Discover apps people built on Collabby by chatting. Run them, then remix to make them yours.
Pascal's Triangle and the Binomial Theorem
Tap cells in Pascal's triangle to see that the entries, the right-and-down lattice paths, and the coefficients of (a+b)ⁿ are all the same combinations.
by Anonymous
Combinations nCr
List every possible selection, divide permutations by r! to strip out order, and see the symmetry of choosing r versus leaving out the rest.
by Anonymous