Common Core: 7.RP.2c
| by: Liza Cope

# Represent proportional relationships by equations

Represent proportional relationships by equations. For example, if total cost t is proportional to the number n of items purchased at a constant price p, the relationship between the total cost and the number of items can be expressed as t = pn.
1. ## Write an equation that represents a proportional relationship between total cost and number of items

Common Core: 7.RP.2c | by: Liza Cope

In this lesson, you will learn how to write an equation that represents the proportional relationship between the total cost and the number of items by finding the unit price.

2. ## Determine the best deal by comparing equations

Common Core: 7.RP.2c | by: Liza Cope

In this lesson you will learn how to determine the best deal by comparing equations that represent the proportional relationship between the total cost, t and the number of items, n.

3. ## Write an equation that expresses the relationship between distance and time

Common Core: 7.RP.2c | by: Liza Cope

In this lesson you will learn how to write an equation that expresses the relationship between the distance and the time by finding the unit rate.

4. ## Compare rates of speed by comparing equations that represent the relationship between distance and time

Common Core: 7.RP.2c | by: Liza Cope

In this lesson you will learn how to compare rates of speed by comparing equations that represent the proportional relationship between the distance, d and the time, t.

5. ## Write equations to represent the proportional relationship between amount of change and final amount

Common Core: 7.RP.2c | by: Liza Cope

In this lesson you will learn how to write equations to represent the proportional relationship between the amount change and the final amount by finding the percent change.

6. ## Calculate simple interest using the simple interest equation

Common Core: 7.RP.2c | by: Liza Cope

In this lesson you will learn how to calculate simple interest by using the simple interest equation.