Easy Mental Subtraction Trick for BIG Numbers

TL;DR

Learn how to mentally subtract large numbers by breaking them into smaller parts and working from left to right.

Transcript

good day welcome to Tech math Channel I'm Josh today we're going to be having a look at how to do mental subtraction of large numbers this video has been a patron suggestion by a guy called Dave who's asked how to do this if you wish to become a patron of the techmath channel I'll going be telling you lots and lots during this video I'm sure but yo... Read More

Key Insights

• 🥳 Mental subtraction of large numbers can be done by breaking them into smaller parts and working from left to right.
• 👻 Adapting the method based on comfort level allows for easier computation.
• 🌥️ Borrowing from the next number across is necessary when the digit being subtracted is larger.

Questions & Answers

Q: What is the first step in mentally subtracting large numbers?

The first step is to start from the left and work your way to the right, just like when saying the numbers out loud.

Q: How can one adapt the method based on their comfort level?

If someone is only comfortable with one-digit subtraction at a time, they can apply this method using only one digit. As they become more comfortable, they can increase to two or even three-digit subtraction.

Q: What should be done if the digit being subtracted is larger than the digit it is being subtracted from?

In such cases, borrowing from the next number across is necessary. The borrowed digit becomes part of the answer, and the subtraction continues.

Q: Is there an alternative method to mental subtraction?

Yes, an alternative method involves approximating the numbers being subtracted. By finding a close approximation, the process can be simplified and made faster.

Summary & Key Takeaways

• The video explains how to mentally subtract large numbers by breaking them up and working from left to right.

• It suggests starting with one-digit subtraction and gradually increasing difficulty based on comfort level.

• The video also demonstrates an alternative method of subtracting by approximating the numbers to make the process easier.