Question

How many 3-digit numbers can you form by using the digits 2,8,5 only once?

Answer 1

Answer:

6

Step-by-step explanation:

a. 285

b. 258

c. 528

d. 582

e. 852

f. 825

Answer 2

Using fundamental principal of counting
The hundred place can be filled by any one of 3 digits in 3 ways.
The tens place can be filled by remaining 2 digits in 2 ways.
The ones place can be filled by remaining one digit by 1 way only.

So total number of 3 digit number can be formed without repetition of the digit = 3 x 2 x 1 = 6 ways