# 2. Add and subtract decimals in a real-world context (A)

teaches Common Core State Standards CCSS.Math.Content.5.NBT.B.7 http://corestandards.org/Math/Content/5/NBT/B/7
teaches Common Core State Standards CCSS.Math.Practice.MP2 http://corestandards.org/Math/Practice/MP2

## You have saved this lesson!

Here's where you can access your saved items.

Dismiss

Card of

Lesson objective: Apply knowledge of adding and subtracting decimal numbers.

This lesson provides an opportunity for students to apply their knowledge and understanding of adding and subtracting decimal numbers to a real-life situation. Students are asked to work out how many items Helen can put in the box without going over a weight limit of 5 lbs.

Key Concept students will use:

• The meanings of addition and subtraction are the same when used with decimals as when used with whole numbers.

Skills students will use:

• adding and subtracting decimal numbers

Students engage in Mathematical Practice 2 (Reason abstractly and quantitatively). Students are able to decontextualize real world situations such as comparing packaging items without exceeding a weight limit and transform them into symbolic representations in a subtraction or addition problem.

Key vocabulary:

• place value
• decomposing
• units of value
• decimal point

Special materials needed:

• Squared paper could be useful if students struggle to keep their digits aligned by place value.
Related content