Question

sum of three consecutive number is 90. find the number

Answer 1

HOPE THIS HELPS...
first number =x
next number x+1
third number x+2
..
x+x+1+x+2=90
3x+3=90
add -3
3x+3-3=90-3
3x=87
divide by 3
3x/3 = 87/3
x=29
the numbers are 29,30,31
..
let the second number be x
the first number = x-1
third number = x+1
..
x+x+1+x-1=90
3x=90
x=30
second number is 30
first & third are 29 & 31 

Answer 2

Let the first number be x
So second number =x+1
3 number=x+2
So ATQ
x+x+1+x+2=90
3x+3=90
3x=90-3
3x=87
x=87/3
x=29