How many numbers can be formed with the digits 1,2,3,4,3,2,1 so that the odd digits always occupy the odd places? Share with your friends Share 0 Neha Sethi answered this Dear student There are four odd digits 1,1,3,3 out of seven digits given to us.Also there are four odd places viz., 1st,3rd,5th,7th.Four odd places can be filled with four odd digits in 4!2! 2!=6 ways,since digits 1 and 3 are repeated.Three even places viz, 2nd,4th and 6th can be filled with three even digits 2,2,4 in 3!2!=3ways.hence total numbers which can be formed=6×3=18. Regards 1 View Full Answer
