Q. Find the number of 4 digit numbers that are formed by using digits 1,2,5,6,7 so that that four digit numbers divisible by 3.

• 24
  If digits are used only once,Out of the given digits, number formed with 1,2,5,7 will be divisible by 3
  Total 4 digit numbers formed=4!=24
• 11 years agoHelpfull: Yes(3) No(0)
• I think its 4!
  because we can use only 1,2,5,7 to be divided by 3.
• 11 years agoHelpfull: Yes(0) No(0)
• any num can be div by 3
  iff its digits sum is div by 3
  so we can consider 1 2 5 7 to make it.(sum=15)
  we can arrange 1257 in 4! ways (bcoz unique digits)
  so ans is 24
• 11 years agoHelpfull: Yes(0) No(0)