How To Subtract In Your Head


Visitors: 499

We all have to subtract numbers sometimes. . . whether it's budgeting your household expenses, checking your change at the store, or installing that new shelving unit during a spot of home DIY.

The problem is, you won't always have a calculator handy.

Well fear not.

Doing simple calculations in your head is just as easy and even faster than using a calculator.

Here's a quick way to do basic subtraction without relying on any electronic gadget. . .

Suppose you offer 50 cents for something costing 18 cents. What's the easiest way to check your change?

50 - 18 = ?

To take 18 from 50, we note that 18 is close to 20, so we take 20 away from 50 (to get 30) and add 2 back on.

Answer: 32

Similarly, in 73 - 49 we decide to take 50 away from 73 and then add 1 back on. We get 24.

Do you see how easy this is? Try these for yourself:

  1. 62 - 36 = ?

  2. 84 - 48 = ?

  3. 71 - 27 = ?

  4. 43 - 16 = ?

  5. 55 - 28 = ?

The above sums are simple. Yet most people would do them the hard way: by working from right-to-left, and trying to remember a “carry digit".

The method you've just learned is based on an ancient formula (or ‘sutra') called “By Addition and Subtraction".

It's simple to learn, and after a few practice runs you'll use it instinctively.

A few tips to help you:

  • Always relax when you're doing mental math (or when performing any mental activity for that matter).

  • Never strain your mind - the natural way is best.

  • And remember, you're only ever competing with yourself. Go at the pace that's most comfortable for YOU!

Like most things in life, there's an easy way and an unlimited number of difficult ways.

Be good to yourself and get used to finding the easy way,

Your whole life will run smoother as a result.

About The Author

Murdo Macleod is co-author of the “Fun With Figures" mental math course, which shows anyone from age 8 and up how to perform lightning-fast mental calculations.


Article Source:

Rate this Article: 
Haunted Lighthouses - Owls Head Light, Owls Head, Maine
Rated 4 / 5
based on 5 votes

Related Articles:

CVS Pharmacy Online Photos and Walgreens Photo Center Go Head to Head

by: Dan Ives (October 17, 2008) 
(Shopping and Product Reviews)

Massage Chair Review Head to Head With the Sanyo HEC SA5000C and the Omega M ..

by: Doug Marks (July 29, 2008) 
(Shopping and Product Reviews)

Home Remedies for Head Louse - Get Rid of Head Lice

by: Dr John Anne (February 11, 2008) 
(Health and Fitness/Home Health Care)

Dish Network vs. DirecTV – Satellite TV Goes Head-To-Head

by: James Taylorthe (March 29, 2007) 

Baby Room Decorating V Nurturing - Head to Head

by: Nell Frances (November 16, 2005) 
(Home and Family/Interior Decorating)

Best Forex Software? A Head-to-Head Comparison

by: Molly Jobs (September 15, 2008) 
(Finance/Currency Trading)

My Child is Scratching His Head Could it Be Head Lice?

by: Thomas T (June 23, 2008) 
(Health and Fitness/Home Health Care)

Forward Head Posture The 42-Pound Head

by: Leon Galleb (March 22, 2012) 
(Health and Fitness/Massage)

Head Shaving: Tips For Shaving Your Head From A Head Shaving Veteran

by: C Mueller (March 29, 2006) 
(Health and Fitness/Mens Issues)

Haunted Lighthouses - Owls Head Light, Owls Head, Maine

by: Denise Villani (May 19, 2008)