Multiply by 7x11x13 Faster Than a Calculator

Ever find yourself needing to multiply by 7x11x13, but don’t have a calculator handy? Don’t worry, there’s a neat trick that can make this calculation a breeze!

The Trick

This method relies on a pattern that makes multiplying by 7x11x13 a simple process. Here’s how it works:

1. Take your number and double it.
2. Subtract the original number from the doubled number.
3. Multiply the result by 11.
4. Add the original number to the product.

Example

Let’s say you want to multiply 23 by 7x11x13:

1. Double 23: 23 x 2 = 46
2. Subtract the original number: 46 – 23 = 23
3. Multiply by 11: 23 x 11 = 253
4. Add the original number: 253 + 23 = 276

Therefore, 23 x 7 x 11 x 13 = 276.

Why Does This Work?

This trick works because of the way the numbers 7, 11, and 13 relate to each other. Multiplying by 7x11x13 is the same as multiplying by 1001. The steps outlined above essentially manipulate the number to make it easier to multiply by 1001.

Practice Makes Perfect

The best way to get comfortable with this trick is to practice. Try it out with different numbers and see if you can get the hang of it. You’ll be surprised how quickly you can multiply by 7x11x13 without a calculator!

Beyond Multiplication

This trick is a great example of how math can be more than just formulas and equations. It demonstrates that there are often shortcuts and patterns that can make calculations easier. Keep an eye out for other interesting math tricks and see what you can discover!