12 Useful Math Hacks That They Didn’t Teach You In School

After finding these math hacks, I’m convinced that all those years of being forced to struggle through math class were just a torture ploy created by evil math teachers everywhere.

Check out these excellent math tips, and you’ll agree! Watch out; you may unleash the inner math whiz you never knew was in you.

01. How To Convert Fahrenheit to Celsius

As if it was this simple all along.

Via reddit/u/quaxon

02. How To Multiply Large Numbers In Your Head

Who knew?

Via imgur / MoonnMan

03. How To Multiply By 11

Finally! I can now multiply more than single digits by 11 in my head.

Via WonderHowTo

04. Secret To Remembering The Numbers In Pi

Also a cool party trick.

Via 1000lifehacks

05. How To Find Fractions Of Whole Numbers

Via imgur / ayounes

06. How To Figure Out What Day Of The Week Falls On What Date.

You might be confused by the picture below, but the math is quite simple (albeit a bit elaborate). You’ll need the codes HERE, which will help you master this.

July has a code of 5.
20th is six because seven goes into 20 twice, which is 14. 20 – 14 = 6.
2069 is two because the leap year code of 2068 is 1, and 2069 is one year after, so that’s 2.

The math can be difficult at first because there are a lot of codes, but it works out incredibly well once you pick it up. Here’s a particular example: January 3, 2014, is a Friday, right? So, January, according to the table, is 6, and we handle days by using multiples of 7. We don’t need to, so it’s just 3 in this case. Next, we need to know the closest leap year, 2012. That has a year code of 1, and 2013 is two years after, so three.We get 6 + 3 + 3 = 12 – 7 = 5! FRIDAY!

Via LifeHacker

07. How To Add And Subtract Fractions

Via imgur / ayounes

08. How To Figure Out Multiples Of Nine

Just count up in the tens column and down in the one’s column.

Via Pinterest / Charles Stirton

09. How To Use Your Hands For 5, 6, and 9 Times Tables

Click HERE for more detailed instruction

Via Instructables / misko13

10. How To Figure Out Percentages

Via Twitter / @LifeHacks

11. How To Remember Which Sign Is Greater Than and Which Is Less Than

Alligator always eats the bigger number!

Via ducksters

12. Use Lines To Multiply

Via school-exercise-books The above is a method used often by the Japanese.

Here is a video demonstrating:

Still don’t have it? Here are three incredible sources that will teach you:

01. Lifehacker, 02. WikiHow, 03. Magical Maths, 04. GameQuarium

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