Subtraction Strategies Using Number Lines

This video tutorial teaches how to solve subtraction problems using a number line. It covers understanding number line scales, common mistakes, and provides examples like solving 74 minus 15. The lesson also includes a real-world application involving calculating height. By the end, viewers will understand how to effectively use number lines for subtraction.

What is the first step in using a number line to solve subtraction problems?

• Count the number of lines

• Add the numbers together

• Identify the starting point

• Choose a random number

What is a common mistake when using a number line?

• Adding instead of subtracting

• Counting the spaces instead of the unit marks

• Ignoring the scale of the number line

• Starting from zero

When subtracting 10 from 75 on a number line that counts by fives, how many jumps are needed?

• One jump

• Two jumps

• Three jumps

• Four jumps

What is the correct result of 34 minus 4 using a number line that counts by ones?

• 33

• 30

• 32

• 31

How do you solve 74 minus 15 using a number line?

• Start at 74, add 5, then subtract 10

• Start at 74, subtract 5, then subtract 10

• Start at 74, add 10, then subtract 5

• Start at 74, subtract 10, then subtract 5

What is an alternative way to solve 74 minus 15?

• Think of 74 as 60 plus 14, then subtract

• Think of 74 as 80 minus 6, then adjust

• Think of 74 as 70 plus 5, then subtract

• Think of 74 as 75 minus 15, then adjust

Why do you need to adjust the result when using the alternative method for 74 minus 15?

• Because 74 is one less than 75

• Because 75 is one more than 74

• Because 15 is more than 10

• Because 74 is a round number

How do you determine Dana's height if she is 13 inches too short for a ride requiring 60 inches?

• Subtract 13 from 60

• Divide 60 by 13

• Add 13 to 60

• Multiply 13 by 60

What is the result of 60 minus 13 using a number line that counts by fives?

• 47

• 50

• 45

• 48

What is the key takeaway from using number lines for subtraction?

• Ignore the number line scale

• Use addition instead of subtraction

• Understand the scale and count spaces

• Always start from zero