Let’s take an Example

283 is a 3 digit number.

 

Digits at hundreds place = 2

Digits at tens place = 8

Digit at units place of = 3

 

So, the number will be

Number = (Digits at hundreds place × 100)
  + (Digits at ten place × 10) + (Digit at units place × 1)

        = 2 × 100 + 8 × 10 + 3 × 1

        = 200 + 80 + 3

        = 283

 

To generalize

Number

Digits are interchanged

Let number be

    abc

 

So, Digit at hundreds place = a

      Digit at tens place = b

  & Digit at unit place = c

 

Number

  = (100 × Digit at hundreds place)  
     + (10 × Digit at tens place)  
      +  (1 × Digit at units place)

  = (100 × a) + (10 × b) + (1 × c)

  = 100a + 10b + c

Thus, number will be

    cba

 

So, Digit at hundreds place = c

      Digit at tens place = b

  & Digit at unit place = a

 

Number

  = (100 × Digit at hundreds place)  
     + (10 × Digit at tens place)  
      +  (1 × Digit at units place)

     = (100 × c) + (10 × b) + (1 × a)

     = 100c + 10b + a

 

Ask a doubt
Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.