Question

A number consists of two digits whose sum is 10.If 18 is subtracted from the number its digits are reversed .find the number.

Answer 1

Hey

Here is your answer,

let the two digit no. be 10x + y.

it is given that x + y =10
this implies y= 10 - x

according to question
(10x + y ) - 18 = (10y + x )

substuting the value of y in above equation we get
x = 6 & y = 4
hence the number is 64.

Hope it helps you!

Answer 2

let the ten's and one's digit be x and y .
A/q,
x+y=10.. (1)
and 10x + y - 18= 10y +x
10x +y - 10y - x = 18
9x - 9y = 18
9(x - y )= 18
x-y= 18/9
x-y= 2... (2)
adding 1 and 2..
x+y+x-y = 12
2x= 12
x = 6
x + y = 10
6 + y = 10
y = 10-6 = 4
req. no. = 10x + y
=64 ans.
if u have any questions regarding this solution .. kindly comment :)