Algebra Readiness Made Easy Grade 4

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Weigh In

Overview

Students examine three scales, each showing the total weight of kids, animals, and

other objects, then solve for the weight of each.

Algebra

Solve two or three equations with two or three unknowns • Replace unknowns with

their values

Problem-Solving Strategies

Reason deductively • Test cases

Related Math Skills

Compute with whole numbers

Math Language

Pounds • Scale • Weigh • Total weight

Introducing the Problem Set

Make photocopies of “Solve the Problem: Weigh In” (page 44) and distribute to

students. Have students work in pairs, encouraging them to discuss strategies they

might use to solve the problem. You may want to walk around and listen in on some

of their discussions. After a few minutes, display the problem on the board (or on the

overhead if you made a transparency) and use the following questions to guide a

whole-class discussion on how to solve the problem:

Look at the three scales. Who are on scale A? (Tom and Smudge the cat)

Who is on scale B? (Tom)

Who are on scale C? (Tom and Alex the dog)

Whose weight do you know for sure? (Tom’s weight)How do you know? (He is the only

one on scale B.)

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