Explaining Subtraction Number Sentences

This lesson teaches how to solve a subtraction number sentence using two methods: base 10 blocks and a number line. The instructor demonstrates how to decompose numbers into hundreds, tens, and ones using base 10 blocks, and then subtracts step-by-step. The same subtraction problem is solved using a number line by making backward jumps in hundreds, tens, and ones. Both methods confirm the correct answer, reinforcing the concept of subtraction through different approaches.

What is the value of a 'long' in base 10 blocks?

• 1

• 1000

• 100

• 10

How many tens can a 100 flat be decomposed into?

• 5 tens

• 10 tens

• 15 tens

• 20 tens

After decomposing a 10 long into ones, how many ones do you get?

• 20 ones

• 15 ones

• 5 ones

• 10 ones

When using a number line, what direction do you move when subtracting?

• Forward

• Backward

• Upward

• Downward

How many hundreds jumps are made when subtracting 342 from 700 on a number line?

• 4 jumps

• 3 jumps

• 2 jumps

• 1 jump