The number of different four digit numbers that can be formed with the digits 2, 3, 4, 7 and using each digit only once is
(A) 120
(B) 96
(C) 24
(D) 100
Answer is (C)
Given digits 2,3,4 and 7, we have to form four-digit numbers using these digits.
∴Required number of ways = 4P4 = 4!=4x3x2x1 = 24
