• 072920 77839
  • info@smartachievers.in
Menu
Back
  • JEE ADVANCE
  • JEE MAIN
  • NEET
  • BITSAT
  • CBSE BOARD
  • UP BOARD
  • CUET
JEE ADVANCE
  • CLASS XI - XII
  • CRASH COURSE
CRASH COURSE
JEE MAIN
  • CLASS XI - XII
  • CRASH COURSE
CRASH COURSE
NEET
  • CLASS XI - XII
  • CRASH COURSE
BITSAT
  • CLASS XI - XII
CBSE BOARD
  • CLASS IX
  • CLASS X
  • CLASS XI
  • CLASS XII
  • CLASS VI
  • CLASS VII
  • CLASS VIII
UP BOARD
  • CLASS IX
  • CLASS X
  • CLASS XI
  • CLASS XII
CUET
  • CRASH COURSE
Courses


Solution


Q.

The total number of six digit numbers, formed using the digits 4, 5, 9 only and divisible by 6, is ________ .          [2023]

Ans.

(81)

Total number of 6-digit numbers formed by the digits 4, 5, 9 and divisible by 6 is when all the digits are same.

444444→6!6!=1

Taking two digits (4, 5), 555444→5!3! 2!=10

For (4, 9), 999444→5!3! 2!=10

Taking three digits: 459444→5!3!=20

559554→5!4!=5,  959994→5!4!=5

959454→5!2! 2!=30

Total number=20+5+5+30+10+10+1=81