Missing numbers in three digit subtraction | Summary and Q&A

TL;DR

Use a number line to solve subtraction equations. Subtract the given numbers from the larger number to find the missing value.

Key Insights

• 🫥 Utilizing a number line can provide visual representation and aid in solving subtraction equations.
• 🌥️ Subtracting values from the larger number helps determine the missing value.
• ❓ In the first example, subtracting 21, 100, and 5 results in a total of 126 subtracted from 621, giving 495.

Transcript

• [Instructor] Let's say that we are told that 495 is equal to 621 minus blank. What would blank be? Pause this video and see if you can figure that out. Okay, now let's do this together, and one technique is to try to visualize this on a number line. 495 is what you get when you subtract something from 621, so let me put those two numbers on a num... Read More

Questions & Answers

Q: How can a number line be used to solve subtraction equations?

A number line helps visualize the subtraction process. By starting at the larger number and subtracting the given values, you can find the missing value.

Q: What is the missing value in the equation 495 is equal to 621 minus blank?

To find the missing value, subtract 21, 100, and 5 from 621, resulting in a total of 126 subtracted. Therefore, the blank is 126.

Q: In the equation blank minus 435 is equal to 210, what is the missing value?

To find the missing value, add 400, 30, and 5 to 210, resulting in a sum of 645. Therefore, the blank is 645.

Q: How can breaking the subtraction process into smaller subtractions help in solving equations?

Breaking the subtraction into smaller subtractions makes it easier to find the missing value. By subtracting small amounts at a time, you can add them up to get the total subtracted or find the larger number.

Summary & Key Takeaways

• The video demonstrates how to solve subtraction equations by visualizing them on a number line.

• To find the missing value, subtract the given numbers from the larger number on the number line.

• In the first example, subtract 21, 100, and 5 to get a total of 126 subtracted from 621, resulting in 495.

• In the second example, add 400, 30, and 5 to 210 to find that 645 minus 435 is equal to 210.