Question

A number Consists of digits the digit at the tens place is twice that of the digit at units place . if 18 is subtracted from the number,the digits are reversed . Find the number.

Answer 1

$\huge \bf \orange{Hey \: there !! }$



Given : If 18 be subtracted from the number, the digits are reversed. 

Solution :

Let the two digit number = 10x + y

And , The number obtained on reversing its digit = 10y + x .

→ The ten's place is 2 times the digit in the unit place.

°•° x = 2y


→ if 18 is subtracted from the number the digits are reversed.

=> 10x + y - 18 = 10y + x

=> 10x - x = 10y - y + 18 .

=> 9x = 9y + 18 .

=> 9x = 9( y + 2 ) .

=> x = y + 2.

[ Replace x with 2y ] .

=> 2y = y + 2 .

=> 2y - y = 2 .

•°• y = 2 .


Then, x = y + 2 = 2 + 2 = 4 .

Therefore , the required number = 10x + y .

= 10 × 4 + 2 .

= 40 + 2 .

$\huge \boxed{ \boxed{ \pink{ = 42.}}}$



✔✔ Hence, it is solved ✅✅.



$\huge \green{ \boxed{ \boxed{ \boxed{ \mathbb{THANKS}}}}}$



$\huge \bf \blue{ \#BeBrainly.}$

Answer 2

$\huge\bf\green {Hey \: there !! }$


▶ Question - A number Consists of digits the digit at the tens place is twice that of the digit at units place . If 18 is subtracted from the number,the digits are reversed . Find the number.


▶ Explanation :-


Let the tens digit be x and unit digit be y


Given tens digit is twice the unit digit


∴ x = 2y ---------- ( 1 )


Let the number be 10x + y


Given 18 is subtracted from the number and the digits are reversed


According to the Question :-


=> 10x + y - 18 = 10y + x


=> 10x + y - 10y - x = 18


=> 9x - 9y = 18


=> 9 ( x - y ) = 18


=> x - y = 2


[ Replacing the value of x ]


=> 2y - y = 2


=> y = 2


Substituting value of y in equation 1 we get :-


=> x = 2y


=> x = 2 × 2


=> x = 4


∴ The Required Number = 10x + y


= 10 × 4 + 2


= 40 + 2


= 42


$\mathbb {\huge{\fcolorbox{yellow}{green}{Hope It Helps}}}$