JEE Main & Advanced
JEE Main Paper Phase-I (Held on 09-1-2020 Morning)
question_answer
If the number of five digit numbers with distinct digits and 2 at the 10th place is 336 k, then k is equal to [JEE MAIN Held on 09-01-2020 Morning]
A)8
B) 6
C)7
D)4
Correct Answer:
A
Solution :
[a] There are eight options on first place (except the digits 0 and 2) and only one option at fourth place (digit '2'). Remaining three places can be occupied by any three digits out of 1, 3, 4, 5, 6, 7, 8 and 9. Number of such numbers \[=8\times 8\times 7\times 6=336\text{ }k\] \[\Rightarrow \,\,\,\,\,\,\,\,k=8\]