The expression "twice the sum of a number and 5" can be translated into a mathematical expression.
Let \( x \) represent the number. The sum of the number and 5 is \( x + 5 \).
Twice this sum would be:
\[ 2(x + 5) \]
This can be expanded to:
\[ 2x + 10 \]
So, the final expression representing "twice the sum of a number and 5" is \( 2x + 10 \).