distinct items can be divided into 3 equal indistinguishable groups in 280 ways. What is the value of ?
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
(3n)!/((n!)^3)/(3!)=280 n=3 satisfies