how many 3 digit numbers can be formed by using 2,4 and 5 such that product of the digits of numbers become even...
a)27 b)26 c)25 d)24

• Product is always even expect only when all digit are 5 hence
  3*3*3= 27
  And subtract unfavourable case
  27-1= 26
• 9 years agoHelpfull: Yes(23) No(2)
• A 3-digit no. is to be formed.
  So no. of digits = 3*3*3 (with repetition ,as no condition is given)
  But, the product of digits has to be even in each case..
  hence, 125 (5*5*5) has to be excluded from those 27 no.s
  Thus, answer is 27 - 1 =26
• 9 years agoHelpfull: Yes(6) No(0)
• ans must be 27=3*3*3-1=26 is ans
• 9 years agoHelpfull: Yes(1) No(1)
• ans must be 27=3*3*3-1=26 i
• 9 years agoHelpfull: Yes(0) No(0)
• 3 can be arranged in 3^3 ways with repetition, so 27
  but it should be mentioned if we can repeat.
• 9 years agoHelpfull: Yes(0) No(0)
• 3*3*3 = 27
• 9 years agoHelpfull: Yes(0) No(1)
• think twice before answering amit..
  3*3*3=27
  two unfavourable cases 245 and 425
  so ans is 27-2=25
• 9 years agoHelpfull: Yes(0) No(8)
• Initially we devide the balls in 4,4,1.
  1st compare group of 4 balls if both group is equal then rest one is defected ball
  else
  
• 9 years agoHelpfull: Yes(0) No(0)
• 27
  each can form 3 three digit number so ans is 3*3*3=27
• 9 years agoHelpfull: Yes(0) No(1)