Find the no f ways you can fill 3x3 grid with 4 corner defined (as a, b, c, d if you have 3 white n 6 blck marbles)
a)9C3 b)5C3 c)9c3+6c3 d)(9c3+6c3)/3!

• got the soln..:D ..check out :
  As the marbles are identical the required answer is 9C3or 9C6 i.e we can start filing the grid either with white or black marbles.
  We have 3 identical white marbles which can be placed in 9 blocks in 9C3 ways and the rest 6 blocks can be filled with 6 white marbles so the required ways of filling the grid is 9C3.
  
  Even if we start filling the 3x3 grid with black marbles the required permutation is 9C6.
  
  so, A) 9C3
  
• 9 years agoHelpfull: Yes(6) No(0)
• their is no condition to fill the grid wiith either white or black marbles. their r 4 corner so we can do
  9c3+6c3
• 9 years agoHelpfull: Yes(2) No(4)
• Simple....the answer will be 9c3 as...all marbles are identical...so there will 9c3 or 9c6 ways to arrange either of marbles and rest are placed automatically.....so the answer is a..9c3
• 9 years agoHelpfull: Yes(2) No(0)