This tip is so easy. It got me through 3rd grade, I used it in Calculus class, and I still use it while working at The Burlap Bag (who am I kidding, I rarely need math here at the shop! It’s fantastic!). BUT if I did need to multiply something by 9, I’d know it super fast.
First, you need to get in your head that your fingers (yes, including thumbs) are numbered from 1-10 starting on the left. Like below:
When you want to multiply 9 by a certain number, put that numbered finger down. So if you want to know 9×7, put down the “7th” finger.
Then count how many fingers are still up to the left of that 7th finger. There should be 6 fingers. That number 6 will be in the “tens” place.
Then count how many fingers are still up to the right of that 7th finger. There should 3 fingers. That number 3 will be in the “ones” place.
Place those two numbers together: 63. 9×7=63.
And you can do this from 9×1 all the way up to 9×10! (for 9×10, there will be 9 fingers up on the left, and 0 on the right. 90!)
Now you don’t need to struggle with remembering those multiplication tables for 9s. And it’s not even cheating, it’s just a helpful hint!
sidenote. We spent Easter afternoon at Zilker, and I decided to take the hand photos then. It’s ridiculously hard to be the hand model and the photographer. We decided I had the best hands to photo. Josiah has a huge blister from gardening. My friend Emily’s hands looked hilarious when she tried to put down just one finger. So I had to be the hand model. And the photographer. Except that I couldn’t click the button or even look through the viewfinder. Real serious issues, I know.
Also, we later had issues with my camera remote. Apparently I had it set to a 2 second delay, which we figured out 5 minutes later. Always check your camera settings. We got this photo:
Josiah: I can get it to work. Maybe if I put my arm up a little higher…
Lauren: I wonder how many Reese’s Easter Eggs I have left at home
Emily: Josiah, freaking give me that thing. Or I will punch you.
In the end, Em took the hand photos for me. And we had a great time at Zilker Park!
(oh and forgive my hair. I’m just a hot mess. But check out that lovely Austin skyline in the background!)