Expression 15 Less 2C6Df0

1. The problem asks us to find the expression that means "15 less than an unknown number." 2. Let the unknown number be represented by the variable $x$. 3. "15 less than an unknown number" means we start with the unknown number $x$ and subtract 15 from it. 4. The correct expression is therefore: $$x - 15$$ 5. The other options mean: - $15 - x$: 15 minus the unknown number (not "15 less than" but "15 minus") - $x + 15$: 15 more than the unknown number - $\frac{x}{15}$: the unknown number divided by 15 6. Hence, the answer is $x - 15$.