Alternative Subtraction Method Concepts

The video tutorial explains how to subtract 23 from 68 using an open number line. It demonstrates counting back by tens and ones, and provides an alternative method of subtracting by first subtracting 20 and then 3. Both methods yield the same result, 45. The tutorial also shows how to verify the subtraction by adding the result back to 23 to get 68.

What is the initial number placed on the open number line?

• 45

• 23

• 68

• 48

What is the purpose of using an open number line in subtraction?

• To visualize subtraction

• To add numbers

• To divide numbers

• To multiply numbers

How many tens are subtracted from 68 in the first method?

• Two tens

• One ten

• Three tens

• Four tens

What is the final result after counting back three ones from 48?

• 47

• 46

• 45

• 44

How can you verify that 23 has been subtracted from 68 using the number line?

• By counting forward

• By multiplying the numbers

• By counting back by tens and ones

• By adding 23 to 68

What is the result of subtracting 20 from 68 in the alternative method?

• 48

• 45

• 50

• 43

What is the final result of subtracting 3 from 48 in the alternative method?

• 45

• 46

• 44

• 47

What is the first step in the alternative subtraction method?

• Subtracting 20 from 68

• Subtracting 10 from 68

• Subtracting 3 from 68

• Subtracting 23 from 68

What is the second step in the alternative subtraction method?

• Subtracting 10 from 48

• Subtracting 23 from 48

• Subtracting 20 from 48

• Subtracting 3 from 48

How does the first subtraction method differ from the second?

• The first method uses multiplication

• The first method uses smaller jumps

• The first method uses larger jumps

• The first method uses addition