Question

The tens digit of a number is twice the unit digit the number obtained on interchanging the digit is 36 less than the orignal number find the orignal number​

Answer 1

ANSWER :-

◾Let the

▪️tenth digit be "10x"

▪️ones digit be "y"

◾Now as given

▪️x = 2y ....(i)

▪️(10x + y) - (10y + x) = 36 ....(ii)

◾Further solving (ii)

⏩We get

▪️9x - 9y = 36 ....(iii)

◾Now by replacing x = 2y

→ 9(2y) - 9y = 36

→ 18y - 9y = 36

→ 9y = 36

→ y = 36 ÷ 9

→ y = 4

◾Now as

▪️x = 2y

→ x = 2(4)

→ x = 8

◾Now the number

= 10x + y

= 10(8) + 4

= 80 + 4

= 84

Answer 2

Tens Digit of a Number is twice the Unit Digit of Number.

Let Unit Digit of Number=x

Then Tens Digit Number=2x

Orignal Number Will be=10(tens Digit)+unit digit

=10×2x+x

=20x+x

=21x

Original Number=21x

When Digit of Original Number is Interchange.

Tens Digit Will be Unit digit=2x

Unit Digit will be Tens Digit=x

Reverse Number=10x+2x=12x

Now

Reverse Number is 36 less than Original.

Means

Original Number-36=Reverse Number

So,

21x-36=12 x

21x-12x=36

9x=36

x=36/9

x=4

Original Number=21x=21×4=84

*Note*

[Now,How Will number

10×(digit at tens place)+Unit Digit.

29 is two digit Number

How it can Written.

10×tens Digit+unit digit

10×2+9

29.]

$\boxed{\mathbf{\huge{Original\:Number=84}}}$