Trick to Multiply Large Numbers close to 100

Quick Multiplication for Numbers Close to 100
When you're multiplying two numbers that are close to 100, there's a handy shortcut that can make the process faster and simpler, especially when doing it mentally. Let's break it down step by step:

1. Determine the Distance from 100
For each number, calculate how far it is from 100.

For example, with 97 and 96:

97 is 3 away from 100 (100 - 97 = 3)
96 is 4 away from 100 (100 - 96 = 4)

2. Calculate the First Part of the Answer
Take one of the numbers (either one works) and subtract the difference of the other number.

Using our example:

97 - 4 = 93 or 96 - 3 = 93

This gives you the first part of the answer: 93

3. Calculate the Second Part of the Answer
Multiply the two differences you found in step 1.

Continuing with the example:

3 x 4 = 12

This is the second part of your answer: 12

4. Combine Both Parts
Put the results from steps 2 and 3 together.

93 (from step 2)
12 (from step 3)

Your final answer: 9312

So, 97 multiplied by 96 is 9312.

[youtooyoutoo]

The method is starting to make 'sense' to me. It seemed quite robust with my random sampling of numbers between 30 & 200 and results between 900 & 40000. I found no errors! (I did not test all 28900 possibilities!) using the algorithm:
C=100-A
D=100-B
E=C+D
F=100-E
G=C*D
H=100F+G
which seems to fit the description. For many of those combinations, there are quicker shortcuts, but these 6 steps are a very practical alternative for most of them. I wish I had found the boundaries for this method, since it seems not as limited as I inferred. There are probably a whole raft of such quixotic tools that don't reflect the standard 'long multiplication & division' reasoning. If someone knows the bounds of this one, that would be fun to know.

[abrenos]

the funny thing about math is not the actual result that matters is how you get there, the way this guy just explained it makes absolutely no sense to me, I have my own way, but for those who do not have any way this is definitely beneficial

[sumerkhanpathan]

Great job sir may Allah bless you and your family Ameen

[imeaniguess.]

Is it different with double digits numbers? I’m getting a semblance of the right answer, but not all the way this way.

[educationforstudents]

I think it will take the same time to solve these types of questions.

[sumerkhanpathan]

Sir give trick for big numbers multiplication and dividation with small numbers.

[BigBoyBlue]

I guess I'm stupid, I even used easier numbers.
Problem: 49 * 51 = ?

Part 1: (100-49) = 51, (100- 51) = 49.
Part 2: 51 + 49 = 100
Part 3: 100 - 100 = 0
Part 4: 51 * 49 = 2499

It feels like I took extra steps to end up doing the exact same thing with a calculator lol

[spacecase]

He's wrong. Maybe it worked with the numbers he chose, but it won't work for others. He should quit learning math from tik tok