Lesson 16

Representing Contexts with Equations

Let’s write equations that represent situations.

Problem 1

Match each situation to one of the equations.

Problem 2

Starting at noon, the temperature dropped steadily at a rate of 0.8 degrees Celsius every hour.

For each of these situations, write and solve an equation and describe what your variable represents.

1. How many hours did it take for the temperature to decrease by 4.4 degrees Celsius?

2. If the temperature after the 4.4 degree drop was -2.5 degrees Celsius, what was the temperature at noon?

Problem 3

Kiran mixes $$\frac34$$ cups of raisins, 1 cup peanuts, and $$\frac12$$ cups of chocolate chips to make trail mix. How much of each ingredient would he need to make 10 cups of trail mix? Explain your reasoning.

(From Unit 4, Lesson 3.)

Problem 4

Find the value of each expression.

1. $$12 + \text-10$$
2. $$\text-5 - 6$$
3. $$\text-42 + 17$$
4. $$35 - \text-8$$
5. $$\text-4\frac12 + 3$$
(From Unit 5, Lesson 6.)

Problem 5

The markings on the number line are evenly spaced. Label the other markings on the number line.