How many three-digit numbers can be generated from 1, 2, 3, 4, 5, 6, 7, 8, 9 such that the digits are in ascending order?
How many three-digit numbers can be generated from 1, 2, 3, 4, 5, 6, 7, 8, 9 such that the digits are in ascending order?
(a) 80 (b) 81 (c) 83 (d) 84
4 views
1 Answers
(d) Any 3 numbers out of 9 can be selected in 9C3 ways.
Now, these three numbers can be arranged among themselves in ascending order in only 1 way.
Hence, total no. of ways = 9C3 × 1 = 84
4 views
Answered