Question

The sum of the digits of a two-digit number is 9. If the digit in tens place is twice the digit in the units place, then the number is:

• A. 36
• B. 54
• C. 63
• D. 45

Answer 1

The correct option is C

63

Let the digit in the units place be $x$.
According to the question, the digit in the tens place is $2x$. Sum of digits is 9.

$\therefore 2x+x=9$
$\Rightarrow 3x=9$
$\Rightarrow x=3$

Hence, the units digit is 3 and the tens digit is $2\times 3=6$.
Thus, the number is 63.