Question

10. If two-digit numbers are formed using the digits 0, 1, 2, 3, 4 without repetition of the digits, then
what is n(S) = ?
(A) 14
(B) 16
(C) 18
(D) 20​

Answer 1

Answer:

B

Step-by-step explanation:

no. of digits =5

no. of 2 digit no.s that can be formed

= 5p2 = 5!/(5-2)!

= 5!/3! = 5×4×3×2×1/3×2×1

=5×4=20

we have to subtract

the 2digit no.s with 0 in tens place =4

20-4=16

10 12 13 14

20 21 23 23

30 31 32 34

40 41 42 43