1. **State the problem:** If 15 is subtracted from the product of 4 and a certain number, the result is 5. Find the number. 2. **Set up the equation:** Let the certain number be $x$. The product of 4 and $x$ is $4x$. Subtracting 15 gives $4x - 15$. According to the problem, this equals 5. 3. **Write the equation:** $$4x - 15 = 5$$ 4. **Solve for $x$:** Add 15 to both sides: $$4x - 15 + 15 = 5 + 15$$ $$4x = 20$$ 5. **Divide both sides by 4:** $$\frac{4x}{\cancel{4}} = \frac{20}{\cancel{4}}$$ $$x = 5$$ 6. **Answer:** The number is $5$.