Mental Addition and Subtraction with Hundreds Charts

The video tutorial explains how to use hundreds charts to mentally add or subtract 10 from a number. It begins with an introduction to the hundreds chart, which consists of 100 boxes arranged in rows of 10. The tutorial demonstrates adding 10 to 167 by visualizing the process on the chart, rearranging rows to simplify the calculation. Similarly, it shows subtracting 10 from 142, again using the chart to visualize and simplify the process. The lesson emphasizes mental math skills and visualization techniques using hundreds charts.

What is the primary purpose of a hundreds chart in this lesson?

• To practice counting by fives

• To learn division techniques

• To help visualize addition and subtraction of 10

• To memorize multiplication tables

How many blocks are there in each row of a hundreds chart?

• 15

• 5

• 10

• 20

When adding 10 to 167 using a hundreds chart, what is the resulting number?

• 157

• 187

• 177

• 167

What is the first step in subtracting 10 from 142 using a hundreds chart?

• Remove 10 ones

• Add a row of 10

• Remove a row of 10

• Add 10 ones

After subtracting 10 from 142, how many tens are left?

• 4 tens

• 5 tens

• 3 tens

• 2 tens