A notebook table includes \((4,\$6)\), \((8,\$12)\), and \((12,\$18)\), with a target of \(15~\text{notebooks}\). Consider these methods: A, build a \(1\text{-}\text{notebook}\) row; B, keep doubling; C, use the nearest row. Choose the method that works, then calculate the cost for \(15~\text{notebooks}\).

The target is exactly fifteen notebooks, so a useful method must reach that quantity rather than overshoot or stop at a nearby row. We’ll evaluate whether each strategy preserves the table’s constant cost per notebook, use a one-notebook rate when needed, and scale to the exact target. Checking against multiple shown pairs will verify the cost.