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:
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.
∴2x+x=9
⇒3x=9
⇒x=3
Hence, the units digit is 3 and the tens digit is 2×3=6.
Thus, the number is 63.