Question

# The two digit number ${\text{x}}$ is the digit at unit place and ${\text{y}}$ is the digit at unit place, then the number is :${\text{A}}.10y + x \\ {\text{B}}.10x + y \\ {\text{C}}.10y - x \\ {\text{D}}.10 - y \$

It is a two digit number ${\text{x}}$ is the digit at unit place and ${\text{y}}$ is the digit at tens place .
Let us take an example of a two digit number $51$ so here $\,1$ is at the unit place and ${\text{5}}$ is digit at the tense place . So here,
$x = 1\,\,\& \,\,y = 5$ ……(i)
We can write $51$ as
$51 = 50 + 1 = 10(5) + 1$
We can write the above equation as $10y + x$ ……(From (i))