Question

b) In a two digit number, the digit in ten's twice the digit in units the
number formed by reversing the digits 36 less than the number. Find
the number?
​

Answer 1

Hey mate,..

Let x = the 10's digit

Let y = the units

then

10x+y = the number

'ten's digit is twice the units digit."

x = 2y

The number formed by interchanging the digits is 36 less than the original number

10y + x = 10x + y - 36

10y - y = 10x - x - 36

9y = 9x - 36

Simplify, divide by 9, results

y = x - 4

From the 1st statement; replace x with 2y

y = 2y - 4

4 = 2y - y

4 = y

then

x = 2(4)

x = 8

84 is the number:

:

:

Check this in the statement:

" The number formed by interchanging the digits is 36 less than the original number."

48 = 84 - 36

48=48

Hope it will help you

Answer 2

Let Digit at Unit Place=X

Then digit at Ten's place=2x

Original Number=10(digit at Ten's place)+(digit at unit place)

=10×2x+X

=20x+X

=21x

Original Number=21x

Reverse=12x

As Reverse of 21=12

Reverse Number is 36 less than Original number.

A/Q

21x-36=12x

21x-12x=36

9x=36

X=36/9

X=4

Original Number=21x=21×4=84

Reverse=12x=12×4=48

Why Number is 10×digit at Ten's place +digit at unit

Consider 59 How it is a Number

When 10×5+9=59

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

$\boxed{\mathbf{\huge{Reverse\: Number=48}}}$