Question

How can we prove the formula n+r-1Cr when r things are to be selected out of n type of things where each object may be repeated any no. of times? OR how can we justify this formula logically?

Answer 1

I hope this will help you
if not then comment me

Answer 2

$\huge{\boxed{\red {\bf{Answer}}}}$

$<b>$
prove  nPr= n!      

                   (n-r)!

and deduce it to nCr answere fast important for test

$\huge\underline{\green {\textbf{prove nPr= n! (n-r)!}}}$

$<font color = purple>$

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