When you face a continuous‑time finance model, you almost always need to find a price, a hedge ratio, or the best trading strategy. The models we have built—from Black‑Scholes to complex interest rate frameworks—often don’t give you a simple formula. This chapter gives you a toolkit: we’ll go through the main ways to get actual numbers from these models, whether by clever algebra, simulating random paths, or solving partial differential equations on a grid. By the end, you will know which tool to reach for and why.