Understanding Thousandths and Addition

This video tutorial covers Unit 5 Lesson 2, focusing on using diagrams to represent addition and subtraction. It explains how to interpret diagrams for numbers, perform addition using diagrams, and align decimals for vertical calculations. The lesson also compares the rates at which two students solve math facts, emphasizing the importance of speed and accuracy. The tutorial concludes with a summary of the key concepts covered.

What does a square represent in the diagram used in Problem 1?

• One thousandth

• One hundredth

• One whole

• One tenth

How many thousandths are represented by five dashes in the diagram?

• Twenty-five thousandths

• Fifty thousandths

• Ten thousandths

• Five thousandths

In the diagram for 216 thousandths, how many longer shapes are drawn?

• Four

• Three

• Two

• One

What is the total value represented by two longer shapes and one square in the diagram?

• Two hundred four thousandths

• One hundred sixteen thousandths

• Two hundred sixteen thousandths

• Three hundred four thousandths

How many dashes are used to represent 304 thousandths in the diagram?

• Four

• Five

• Three

• Two

What is the first step in adding 137 thousandths and 284 thousandths using diagrams?

• Add the hundredths

• Trade squares for longer shapes

• Bundle the thousandths

• Add the tenths

After bundling, how many squares are left in the hundredth section?

• Four

• Two

• Three

• One

What is the final sum of 137 thousandths and 284 thousandths?

• 421 wholes

• 421 hundredths

• 421 tenths

• 421 thousandths

How is the reasoning in the first two questions similar?

• Both involve multiplication

• Both involve subtraction

• Both involve division

• Both involve grouping and trading

Which method was faster, 2a or 2b?

• Both were the same

• 2a

• 2b

• Neither was fast