Question

Consider all the 5 digit numbers where each of the digits is chosen from the set { 1, 2, 3, 4} . Then the number of numbers , which contains all the four digits is:

• A. 240
• B. 244
• C. 586
• D. 781

Answer 1

The correct option is D 781

5 digit numbers where each of the digits is chosen from the set { 1, 2, 3, 4} . Then the number of numbers , which contains all the four digits is

Repeatation allowed

No. of ways $=4\times 4\times 4\times 4\times 4=1024$

Let us eliminate 1 no.

$\therefore$ No. of ways$=4\times 3\times 3\times 3\times 3\times 3=243$

Answer$=1024-243=781$