IB Project: Multiply and Divide Decimals

Show your level of understanding for multiplying and dividing decimals by completing each of

the following four tasks. Be sure to follow all directions. For each activity, show all of your work

mathematically as well as explain clearly what you are doing. Organize and write neatly – a

paper that can’t be read or followed can’t be graded.

Part 1: Comparing Decimals (pg. 55)

Part 2: How Fast?

Part 3: Variation: What’s Your Multiplication Strategy? (pg. 98)

Part 4: Who’s Correct?

Criterion A: Knowing and understanding

Maximum: 8

At the end of year 1, students should be able to:

i. select appropriate mathematics when solving problems in both familiar and unfamiliar situations ii. apply the selected mathematics successfully when solving problems iii. solve problems correctly in a variety of contexts.

Achievement level Level descriptor

0

The student does not reach a standard described by any of the descriptors below.

1–2

The student is able to:

i. select appropriate mathematics when solving simple problems on comparing

decimals in familiar situations

ii. apply the selected mathematics successfully when solving

multiplication and division of decimals problems

iii. generally solve these problems correctly.

3–4

The student is able to:

i. select appropriate mathematics when solving more complex problems on

comparing decimals in familiar situations

ii. apply the selected mathematics successfully when solving

multiplication and division of decimals problems

iii. generally solve these problems correctly.

5–6

The student is able to:

i. select appropriate mathematics when solving challenging problems on

comparing decimals in familiar situations

ii. apply the selected mathematics successfully when solving

multiplication and division of decimals problems

iii. generally solve these problems correctly.

7–8

The student is able to:

i. select appropriate mathematics when solving challenging problems on

comparing decimals in both familiar and unfamiliar situations

ii. apply the selected mathematics successfully when solving

multiplication and division of decimals problems

iii. generally solve these problems correctly.

Comparing Decimals

In each pair of numbers, circle the one that is larger.

Show your work here.

Explain your process for deciding which numbers were larger.

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How Fast?

Solve this problem. Remember to show your step by step process clearly.

Imagine you have been driving over the mountains. It is a twisting, turning road and you are not

going very fast. In fact, after 1.5 hours, you’ve only gone a total of 16.5 kilometers. How many

kilometers per hour have you been traveling?

Who’s Correct?

Solve this problem. Remember to show your step by step process clearly.

Emma and Robert had a set of rational numbers written in different formats to put in order

from least to greatest. Emma said that her list was correct, but Robert noted differences in the

results and said that his list was correct. Who organized the numbers correctly? Be sure to

explain your answer in detail.

0.125 9

8 1.001 1

2

13

Emma’s List Robert’s List