0 votes 0 votes Suppose a 6 digit number N is formed by rearranging the digits of the number 123456. If N is divisible by 5, then the set of all possible remainders when N is divided by 45 is (A) {30} (B) {15, 30} (C) {0,15,30} (D) {0, 5, 15, 30} Combinatory combinatory + – . asked Mar 26, 2017 retagged Jun 27, 2017 by Arjun . 1.3k views answer comment Share Follow See all 4 Comments See all 4 4 Comments reply Tesla! commented Mar 29, 2017 reply Follow Share Its an ISI question please someone add appropriate tag 0 votes 0 votes s9k96 commented Mar 29, 2017 reply Follow Share What's ISI ? 0 votes 0 votes Tesla! commented Mar 29, 2017 reply Follow Share Indian Statistical Institute. 0 votes 0 votes Tesla! commented Apr 2, 2017 reply Follow Share Its an amazing question total 120 combination are there have tried 10 and getting 30 as remainder, answer is either a or b but not which one 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes answer is option a) {30 }, bcoz no. is divisble by 5 ( i.e last digit is fixed ) , so we have to find remainder when no. is divive by 45 , for this first divide the no. by 5 and then divide the resultant by 9 and any no. is divisible by 9 if its sum is divisible by 9. So (1+2+3+4+6)%9 = 6 . so remainder is 6*5 = 30 Rajni answered Apr 21, 2017 Rajni comment Share Follow See 1 comment See all 1 1 comment reply Shweta Nair commented May 3, 2018 reply Follow Share The remainder is coming out to be 7.How did you get 6? And why did you not include 5 while adding the digits? 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes N = 45q + r q and r are quotient and remainders rsep. now reduce the whole equation to modulus 9 N = r = 3 (mod9) and the only possible value for such an "r" is 30 = 3 (mod9) kratos answered May 1, 2019 kratos comment Share Follow See all 0 reply Please log in or register to add a comment.