WATCH: Genius maths hacks: Multiplying teen numbers

By the end of grade 4, sometimes grade 3, kids are expected to learn and know their times tables off by heart. It’s usually only the 1 to 12 times tables, but considering that’s over 140 combinations to memorise in the early stages of primary school, we can’t help but wish there was an easier way to work out your times tables if they happen to slip your mind. With that we created our genius maths hacks series. 

Also see: WATCH: Genius maths hacks: The 11 times table

Our latest video (scroll up to see), multiplying teen numbers, was inspired by a hack sent in by one of our readers, Jack Greenblatt. 

“Say 19x18,” he started. 

“Do 19+8=27 then add a 0 on the end. Thus 270. 

Then take the two end units and multiply them. 9x8=72. 

Then 270+72=342. 

Can be done for 11x11 right up to 19x19.”

via GIPHY

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Do you have any other maths hacks? Tell us and we could share it with our readers?

Also see:

• WATCH: Genius maths hacks: The 9 times table
• WATCH: This DIY is the easiest and simplest way to learn fractions
• The "life-changing" math hack for percentages they probably didn’t teach you in school