Question

The ratio between a two-digit number and the sum of digits of that number is $4:1$. If the digit in the unit place is $3$ more than the digit in the ten's place, what is the number?

• A. $63$
• B. $36$
• C. $24$
• D. $40$

Answer 1

The correct option is B $36$

Let us assume that digits of the number are $x$ and $y$ with $x$ on ten's place.

$\therefore$ Number is $10x+y$

Given that, digit on unit's place is $3$ more than ten's place, i.e. $y=x+3$ ......(1)

Also,

According to the question,

$10x+y:x+y=4:1$

$\Rightarrow 10x+y=4x+4y$

$y=2x$

Substituting in $\left(1\right)$, we get $2x=x+3$

$\therefore x=3,y=6$

The number is $36$.