Question

The ten’s digit of a two digit number is three times the unit digit . The sum of the number and the unit digit is 32 . Find the number.

Answer 1

Let the tens digit be x and units digit be y. So, the number is 10x+y. x=3y (given)...........(eq.1) 10x+y+y=32 (given) Substituting the value of x from eq. 1, 10(3y)+y+y=32 30y+y+y=32 32y=32 y=1 So, x=3y=3×1=3 Hence , the number is 31

Answer 2

let unit digit be= x then
ten's digit =3x
sum of the number =[10{3x}+1{x}]
sum of the number and the unit digit=32

[10{3x}+x]+x=32
30x+x+x=32
x=1

so,by putting the value of x we get
ten's digit =3
unit digit=1
so the number is 31