Comments on: 5 Easy to Remember Mathematical Tricks You Can’t Live Without

By: Applied Colors

Applied Colors — Wed, 23 Dec 2009 20:14:09 +0000

Yes! Practical math. I have bookmarked and social bookmarked this page.

By: Reg

Reg — Sat, 18 Apr 2009 07:20:30 +0000

Rounding and metric advantages. The guy at the register was away at the phone when I plonked the bananas on his scales and found they weighed 700 grams. I glanced over at the price on the rack and they were $2.99 @ kg. That’s a 1000 grams if you’re not sure. Round up to $3.00 a thousand and 3 x 7 = 21 so they cost $2.21. Even the Chinese guy was amazed.

By: JD Long

JD Long — Fri, 28 Nov 2008 02:51:50 +0000

More handy shortcuts I learned living in Belgium 4 years:

1.) 5 miles is almost exactly equal to 8 kilometers. So 55mph is 88 kph. Going 50 miles is 80 klicks.

2.) To approximate temperature conversions, take your celcius temperature, double it, and add 32. If the temperature is 20 C, double it (40) and add 32, which makes it 72 degrees F. However, this does NOT work if the temperature is below freezing.

~~JD~~

By: Jeff Barnett

Jeff Barnett — Thu, 27 Nov 2008 23:38:13 +0000

Thanks, Matt. I’m always up for different presentations for different learners.

By: Matt S.

Matt S. — Thu, 27 Nov 2008 20:15:02 +0000

Hey Jeff, good article. I just wanted to say that in Tip #1, you break down the distributive property like so:

24 * 12 = (24 * 10) + (24 * 2) = 240 + 48 = 288

While that’s easy to understand for those of us who are mathematically inclined, you might miss your target audience with that explanation. It might be easier to explain it with:

24 x 12 = 288
24 x 10 = 240
24 x 2 = 48
240 + 48 = 288

By: The Midnight Hour - » Math Tricks on Primer

The Midnight Hour - » Math Tricks on Primer — Mon, 24 Nov 2008 18:23:37 +0000

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