## How do you find the rate of change in relation?

In related-rate problems, you find the rate at which some quantity is changing by relating it to other quantities for which the rate of change is known….Solution

- We seek dhdt. Now V=13πh3, and therefore dVdh=πh2.
- We have seen that r(t)=h(t). Thus, when h=60, we have drdt=1120π cm/s.
- We seek dSdt.

### What is related rates used for?

Related rates and problems involving related rates take advantage of quantities that are related to each other. Related rates help us determine how fast or how slow a certain quantity is changing using the rate of change of the second quantity.

#### What are the five steps to solve a related rate problem?

To summarize, here are the steps in doing a related rates problem:

- Decide what the two variables are.
- Find an equation relating them.
- Take d/dt of both sides.
- Plug in all known values at the instant in question.
- Solve for the unknown rate.

**Why are related rates called related rates?**

This is the core of our solution: by relating the quantities (i.e. A and r) we were able to relate their rates (i.e. A′ and r′ ) through differentiation. This is why these problems are called “related rates”!

**What are the steps in solving a related rates problems?**

## How are related rates used in the real world?

Supposedly, related rates are so important because there are so many “real world” applications of it. Like a snowball melting, a ladder falling, a balloon being blown up, a stone creating a circular ripple in a lake, or two people/boats/planes/animals moving away from each other at a right angle.

### How do you solve basic related rates?

- Draw a picture of the physical situation. Don’t stare at a blank piece of paper; instead, sketch the situation for yourself.
- Write an equation that relates the quantities of interest.
- Take the derivative with respect to time of both sides of your equation.
- Solve for the quantity you’re after.

#### What is a related rates problem?

Related rates problems are word problems where we reason about the rate of change of a quantity by using information we have about the rate of change of another quantity that’s related to it.

**How do related rates problems arise give an example?**

If two related quantities are changing over time, the rates at which the quantities change are related. For example, if a balloon is being filled with air, both the radius of the balloon and the volume of the balloon are increasing.