Question

In a three digit number the tens digit is thrice the unit digit and the hundreds digit is four times the unit digit. Find the number if sum of its digit is16

Answer 1

862 is answer.

Let u = units digit

Let t = tens digit

Let h = hundreds digit

given:

(1) t=3u

(2)h=4u

(3) u+t+h=16  

Substitute (1) and (2) into (3)

(3) u+3u+4u=16

(3) 8u=16

(3) u=2

and

(1) t=3u

(1) t=3*2

(1) t=6

and

(2) h=4u

(2) h=4*2

(2) h=8

The number is:

862