One Dominoes (2*1) can be placed on two adjacent squares in a Chess board.
How many dominoes can be placed in an 8 * 8 chess board if a row is already filled and cannot be used for placing Dominoes?

• 28
  its like you can have them placed horizontally or vertically.
  now placing them horizontally gives you 7*(8/2)
  you could have done the same in vertical arrangement:
  can be done in (6/2)*8 ways, leaving one horizontal row.
  hence 8*3+4 = 28
• 11 years agoHelpfull: Yes(3) No(2)
• tota no.of dominoes can be filled in 8*8=64/2=32
  since one row is filled therefore no.of dominoes=32-4=28
• 11 years agoHelpfull: Yes(3) No(1)
• 18 dominoes
• 11 years agoHelpfull: Yes(1) No(11)
• each of them can be placed horizontally, so each row contains 4 dominoes.
  as 1 row is already filled, so remaining 7 rows contain 7*4=28 dominoes.
• 10 years agoHelpfull: Yes(1) No(1)