7th Grade Math

GLE 0706.1.2 Apply and adapt a variety of appropriate strategies to problem solving, including estimation,

and reasonableness of the solution. Also addresses GLE 0706.5.2, SPI 0706.5.1, SPI 0706.5.2.

532 Statistical Displays

More Statistical Displays

PART A BC

Multi-Part

Lesson 4

Understand You know the number of gallons of

the tank. You need to predict the

number of tablespoons of sea salt.

Tank Capacity (gal) 15

10

20

5

0 1 234567891011

25

30

35

40

45

50

Sea Salt (tbsp)

x

y

(1, 5)

(2, 10)

(3, 15)

(4, 20)

(5, 25)

(6, 30)

Plan Organize the data in a graph so

you can easily see any trends.

Solve Continue the graph with a dotted

line in the same direction until you

align horizontally with 50 gallons.

Graph a point. Find what value of

sea salt corresponds with the point.

Ten tablespoons are required for

a 50-gallon tank.

Check Find the unit rate of tablespoons of sea salt per gallon of water. Multiply the unit

rate by the number of gallons to find the number of tablespoons of sea salt.

0.2 tbsp salt

_1 gal water ×

50 gal water

_ 1 = 10 tbsp salt ✓

Use a Graph

TESS: I recently Sea Salt Requirements

Tablespoons

of Sea Salt^123456

Capacity of

Tank (gallons) 5 1015202530

purchased a saltwater

aquarium. I need to

add 1 tablespoon of

sea salt for every

5 gallons of water.

YOUR MISSION: Use a graph to predict the number of tablespoons

of salt required for a 50-gallon saltwater fish tank.

Main Idea Solve problems by using a graph.

1. Suppose the tank holds 32 gallons. Predict how much sea salt is required.

Problem-Solving Investigation

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