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6.06 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

MA.4.NSO.2.6

Identify the number that is one-tenth more, one-tenth less, one-hundredth more and one-hundredth less than a given number.

MA.4.NSO.2.7

Explore the addition and subtraction of multi-digit numbers with decimals to the hundredths.

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