To represent "three less than half a number," let's break it down step by step:

1. "Half a number" translates to $\frac{x}{2}$, where $x$ represents the number.
2. "Three less than" means subtracting 3 from this value.

Thus, the expression becomes: $\frac{x}{2} - 3$

Example Answer:

The correct expression is $\frac{x}{2} - 3$.

Would you like a deeper explanation of how this is derived or examples of its application?

Here are some related questions to deepen your understanding:

1. How would the expression change if it said "three more than half a number"?
2. What if the expression said "three less than a third of a number"?
3. Can you rewrite $\frac{x}{2} - 3$ in an equivalent form using decimals?
4. How can this expression be used in solving word problems?
5. What is the result when $x = 10$ in $\frac{x}{2} - 3$?

Tip: Always work step-by-step, translating each part of a phrase into a mathematical expression.