Question

find three consecutive numbers whose sum is 81

Answer 1

A+(A+1)+(A+2)=81
By solving this equations, We get A= 26
Thanks

Answer 2

let three consecutive numbers be

X, X+1, X+2
then
$x + x + 1 + x + 2 = 81 \\ 3x + 3 = 81 \\ 3x = 81 - 3 \\ 3x = 78 \\ x = 78 \div 3 \\ x = 26 \\ \\ x$
then.....
X+1=26+1=27
X+2=26+2=28....
three consecutive numbers=
$26 \: 27and28$
hope this helps you....