Question

The difference of digits of a 2 digit number is 3.The number formed by interchanging the digits when added to the number gives 77. What is the number

Answer 1

Answer:

Let a digit be x (no matter units place or tens digit place) the the other digit will be 3x. Since 3x has to be a single-digit non-zero no. so x can only be either 1,2 or 3.

So the no. is (let it be ‘a’) a= x _3x (Now assuming x to be tens digit..You can also take it as units digit).

Then according to the question:

interchanged no. (let it be ‘b’) b= 3x_x.

now,

a+b=88 ……..(Given)

Since x can only be 1,2 or 3.

so addition would take no carry on.

so a+b=4x_4x=88.

comparing both places:

4x=8

and 4x=8.

(both equations are same)

so x=2.

So no. is either 26 or 62.

You can also see a=10*x+3x=13x

(As a 2-digit no. is of the form 10a+b,where both a,b are single digit no.s ‘a’ not equal to 0. )

similarly b=10*3x+x=31x

a+b=44x=88.

x=2.

so a=26 (or 62 according to what you have taken as tens digit.)