Final answer:
To translate 'twelve less than triple a number' into an algebraic expression, define 'a number' as x, triple it to get 3x, and then subtract 12 to arrive at the expression 3x - 12.
Step-by-step explanation:
The given written expression 'twelve less than triple a number' can be translated into an algebraic expression. First, let's define 'a number' as the variable x. The word 'triple' suggests that we will multiply this number by 3, yielding 3x. 'Twelve less than' indicates that we need to subtract 12 from this product. Therefore, the complete expression is 3x - 12.