Question

3 number whose average is 112,the first number is 1/6th the sum of other 2.what is the first number?

Answer 1

average of 3 numbers is112

sum of numbers =3×112=336

let the numbers be x, y, z

x+y+z=336

(y+z) /6=x

instead of x we can write (y+z)/6

(y+z) /6+y+z=336

multiple each term by6

y+z+6y+6z=336

7y+7z=336

divide by 7

y+z=48

x=(y+z) /6

=48/6

=8