# Fun Pattern squaring numbers whose digits are all ones

Taught by YourMathGal
• Currently 3.0/5 Stars.
4365 views | 7 ratings
Meets NCTM Standards:
Lesson Summary:

This lesson explores a unique pattern for multiplying numbers by themselves (squaring) if all its digits are 1. By using the pattern, it's possible to solve complex calculations without a calculator. For example, by counting up to the number of ones and then back down to 1, you can solve any number up to 9 ones in a row. It's a fun and useful trick that can be shared with friends and family.

Lesson Description:

A fun pattern for multiplying numbers by themselves (squaring) if all its digits are 1....like 11 x 11 or 11111 x 11111, etc. Show your friends!

More free YouTube videos by Julie Harland are organized at http://yourmathgal.com

• What are some fun number patterns?
• What is the pattern when all ones are squared?
• What is 111^2, 11111^2, and 111111111^2?
• #### Staff Review

• Currently 3.0/5 Stars.
This lesson is a cute little trick for squaring numbers that have only 1s in them. The pattern is pretty cool, and it works all the way up to 111111111^2.
• #### alphasentaury

• Currently 4.0/5 Stars.
What about numbers with more than 9 1s in them?
• #### rsand

• Currently 4.0/5 Stars.
I think she's fun! That's cool ^^