Question

find three consecutive number whose sum is 81

Answer 1

Let the three number be x,(x+1) and (x+2).
Then,
x+(x+1)+(x+2)=81
3x+3=81. ....divide by 3
x+3=27
x=27-3
x=24.
Then the other two numbers are :(x+1)=25 and (x+2)=26.

Hence the three consecutive numbers are 24,25 and 26.

Answer 2

let the no be x

the 2nd consecutive no will be x+1

3rd consecutive no will be x+2

according to the question,

x+x+1+x+2=81

3x+3=81

3x=81-3

3x=78

x=78/3

x=26

1st no = x= 26

2nd consecutive no = x+1 = 26+1 = 27

3rd consecutive no = x+2 = 26+2 = 28

verification:

26+27+28=81

hence, verified .

hope my answer is helpful :)