Question

the sum of the digit of a two digit number is 9 the time the number in time unit digit find the number​

Answer 1

Let ones digit number be y 

and tens digit number be x

where, x>y

according to question

x=6y....... (1)

and x +y = 9

6y +y=9

7y= 9

y=9/7

putting the value of y in equation (1)

x=6*9/7

x=54/7

so x=54/7 and y=9/7

Answer 2

Answer:

let the digit at tens place = x

.......................... ones place = y T O

Number = 10x + y x y

x + y = 9 10x + y

on Reversing = 10y + x

9 ( 10x + y ) = 2 (10y + x ) T O

90x + 9y = 20y + 2x Y X

88x = 11y 1oy + x

8x = y

= x + 8x = 9

9x =9

x = 1

= y = 8x = 8×1

= y = 8

Number = 10x + y

= 10 × 1 + 8

= 10 + 8

ANSWER = 18