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6.01 Add decimals

Lesson

Are you ready?

Do you remember how to use the standard algorithm to add numbers together? Let's try this problem to practice.

Find the value of $285+113$285+113.

Vocabulary:
  • You might notice that sometimes the standard algorithm is called the 'vertical algorithm'. Let's think about why. When we use the standard algorithm, we line our numbers up in 'vertical' place value columns.

Learn

This video shows us how to add numbers with decimals using the standard algorithm.  

Apply

Question 1

Find $0.15+0.61$0.15+0.61 giving your answer as a decimal.

 

Learn

This video shows us how to continue patterns with decimals using addition. 

Apply

Question 2

Consider the following pattern.

  1. What is the pattern?

    $0.03$0.03 $0.12$0.12 $0.21$0.21 $\editable{}$ $\editable{}$ $\editable{}$

    The numbers are increasing by $9$9.

    A

    The numbers are increasing by $0.9$0.9.

    B

    The numbers are increasing by $0.09$0.09.

    C

    The numbers are increasing by $90$90.

    D
  2. Now complete the pattern.

    $0.03$0.03 $0.12$0.12 $0.21$0.21 $\editable{}$ $\editable{}$ $\editable{}$

 

Remember!

When setting up the standard algorithm for numbers with decimals, we must line up the decimal points so that we are adding digits with the same place value.

 

Outcomes

5.NBT.B.7

Add, subtract, multiply, and divide decimals to hundredths, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between operations. Assess the reasonableness of answers using estimation strategies. (Limit multiplication problems so that the product does not exceed thousandths. Limit division problems so that either the dividend or the divisor is a whole number.)

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