Exploring Adding and Subtracting Decimals

What is the learning target for this math talk?

• To understand the concept of fractions

• To learn about geometry shapes

• To add and subtract decimals to the thousandths place

• To memorize the multiplication table

Tags

CCSS.5.NBT.B.7

What problem are students asked to solve?

• 54.6 + 29.99

• 54.6 x 29.99

• 54.6 - 29.99

• 54.6 / 29.99

Tags

CCSS.6.NS.B.3

What is a 'friendly number' as mentioned in Maya's strategy?

• A number that is hard to subtract

• A number in a complex equation

• A prime number

• A number that is easy to subtract

Tags

CCSS.1.OA.A.1

How did Maya find the distance between the two numbers?

• By multiplying

• By dividing

• By subtracting and jumping to benchmark numbers

• By adding

Tags

CCSS.2.MD.B.6

CCSS.1.NBT.C.4

What did Darren use to help him think about the problem?

• Money

• Shapes

• Animals

• Colors

Tags

CCSS.2.OA.A.1

How did Darren find the difference between the two numbers?

• By using an algorithm

• By drawing a diagram

• By adding up from the smaller number

• By subtracting directly

Tags

CCSS.1.OA.A.1

What is the first step in subtracting decimals using the U.S. standard algorithm?

• Subtract the ones place first

• Start with the largest place value

• Align the decimal places

• Multiply the numbers

Tags

CCSS.6.NS.B.3

What do you need to do if you cannot subtract in a certain place value?

• Skip it

• Guess the answer

• Decompose a higher place value

• Stop and ask for help

Tags

CCSS.2.NBT.B.7

What was the final answer to the problem given in the lesson?

• 24.71

• 24.61

• 25.61

• 23.61

Tags

CCSS.5.NBT.B.7

Why is it useful to line up the decimal places when subtracting decimals?

• To ensure correct subtraction of place values

• It's not actually useful

• To make the numbers look neat

• Because it's easier to add this way

Tags

CCSS.5.NBT.B.7