# How to become better at mental math

How to Get Better at Math (While Spending Less Time Studying)

10 Tips to Improve Your Mental Math Ability. Add and Subtract From Left to Right. Remember how you were taught in school to add and subtract numbers from right to left (don’t forget to carry the. May 12,  · If it's simply that your child just needs more practice at mental math, you can encourage them to put their mental math skills to use in different ways: Practice Tricks and Strategies Mental calculations involve using specific techniques created for solving specific types of problems, rather than memorizing the answers to equations.

Ever dreamed of being able to multiply numbers lickety-split…and completely in your head? Wouldn't it be great if you could quickly solve problems like 36 x 25 and 47 x 24? Good news—you can! Keep on reading to find out how. Now that we've learned the basics of lightning fast mental addition, mental subtractionand mental multiplicationit's time to turn our attention to a few tips that will help you take your skills to the next level.

Today we're going to kick things off by learning 5 tips that will help you multiply numbers quickly in your head and become the mental math wizard in your family. How to multiply by powers of 5 How to square numbers ending in 5 How to easily multiply 9s How to multiply by powers of 2 How to double and halve numbers quickly As an Amazon Associate and a Bookshop. Tip 1: How to Multiply by Powers ay 5 There are times in life when you just get lucky. It turns out that one of those lucky little moments occurs each and every time you need to matb one number by another number that happens to be a power of 5.

For example, let's say you need to find 36 x 5 which, of course, fits the bill since 5 is the first power of 5. Why is that helpful? Because it means that we can find 36 x 5 by instead finding 36 x 10 which is easy and then dividing the result by 2.

Impressively speedy, right? But we're not done! What if we instead need to solve the problem 36 x 25? So how does it work in this case? And in mzth, the trick with powers of 5 is to recognize that they are always some multiple of 10 divided by an integer. We talked about how to square numbers in your head before, but it turns out that things get a whole lot easier when squaring a two-digit number that ends in 5.

Here's the trick: Any time you square a two-digit number how to pass a crack drug test ends in 5, the last digits of the answer will be 25 and the digits before that are given by multiplying the first digit of the number by the number that's one brcome. Well, once again we know that the last two digits will be 25 since they what is an mpx file are for this kind of problemand the previous digits are given by 7 x 8 that's the first digit times the number that's one greater.

Fast and easy! Tip 3: How to Easily Multiply Lots of 9s The third trick for today has to do with multiplying any number by 9, 99,or any other number that's 1 less than a power of What makes all of these wild 9 numbers special? The distributive property of multiplication tells us that this is the same as 44 x 10 - And since it's easy to multiply by a power of 10, looking at the problem this way makes it much easier to solve.

In other words, any time you're multiplying by one of these numbers that are all 9s, the trick is to know that you can simply multiply the other number by the next higher power of 10 and then subtract the original number.

Give it a try and you'll see just how much faster this is. Tip 4: How to Multiply by Powers of brtter You can use today's fourth tip any time you're multiplying one number by another number that's a power of 2. Which means that any time you're multiplying some number by 2, 4, 8, 16, 32, 64, and so on, this is your ticket to mental math bliss. Instead of going through the usual multiplication process, in this case all you have to do is double the number you're multiplying for each power of 2 in the how to get my cat to stop biting cords number.

Which means that we can quickly find the answer by continually doubling 12 three times. So the first doubling of 12 gives 24, the second doubling takes us to 48, and tp third doubling gives Tip 5: How to Double and Halve to Multiply Fast The previous trick is really mathh a special case of today's fifth and final and I think coolest trick that you can use whenever brtter of the numbers you're multiplying is even.

Let's say you're multiplying 47 x Since 24 is an how do i get to blasted lands number, let's use the idea of doubling and halving to solve this problem quickly.

What do I mean by doubling and halving? Well, the trick is to continually double one number while halving the other. In this case, this means that we turn the problem 47 x 24 into the problem 94 x 12 by simultaneously doubling 47 and halving We can then do the same thing and turn the problem into x 6, and again to get x 3. At this point, we can't double and halve any further, so we just have to do the remaining—much easier! Wrap Up You'll definitely need how to become better at mental math practice these techniques to get comfortable and fast using them—so I highly encourage you to make up some multiplication problems to work through.

It will take some time and energy, but your effort will certainly be rewarded! Finally, please send your math questions my way via FacebookTwitter mentwl, or email at mathdude quickanddirtytips. Thanks for reading, math fans! Mental math image from Shutterstock. He provides clear explanations of math terms and principles, and his simple tricks for solving basic algebra problems will have even the most math-phobic person looking menal to working out whatever math problem comes their way.

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How to multiply by powers of 5 How to square numbers ending in 5 How to easily multiply 9s How to multiply by powers of 2 How to double and halve numbers quickly. As an Amazon Associate and a Bookshop. About the Author. Follow Facebook Linkedin. Subscribe Podcast Google Stitcher. You May How to create business rules in database Like How to Multiply Quickly.

The Math Dude. How to Multiply Any 2-Digit Number by

As your mental math skills improve, challenge yourself to make closer approximations and take on harder calculations. The key to improving your mental maths is through disciplined regular practice. How do I become super-fast at mental math? Take 10% of a = \$ Take 5% of the \$10 = \$5. Finally, take 2,5% of the \$5 and that gives you \$##.

Last Updated: April 5, References. This article was co-authored by Daron Cam. Daron has over eight years of teaching math in classrooms and over nine years of one-on-one tutoring experience. Mary's College. There are 9 references cited in this article, which can be found at the bottom of the page. This article has been viewed 88, times. Eventually, you'll find yourself in a situation where you'll have to solve a math problem without a calculator. Trying to imagine a pen and paper in your head often doesn't help much.

Fortunately there are faster and easier ways to do calculations in your head—and they often break down a problem in a way that makes more sense than what you learned in school.

Whether you're a stressed-out student or a math wizard looking for even faster tricks, there's something for everyone to learn. One way to improve your mental math skills is to memorize your multiplication and division tables, so you always have the answer to those problems instantly.

Learn why people trust wikiHow. Download Article Explore this Article methods. Tips and Warnings. Related Articles. Article Summary. Method 1 of All rights reserved. This image may not be used by other entities without the express written consent of wikiHow, Inc.

Add the hundreds, tens, and ones places separately. Thinking in "hundreds" or "tens" instead of single digits will make it easier to keep track when digits sum to more than ten. Method 2 of Adjust to get round numbers, then correct after the problem is done.

Round numbers are much faster for most of us to work with. Keep a mental note of the changes you made so you can adjust to get the exact answer at the end. Undo the rounding by subtracting 4 from to get Subtraction : For - , break it up into - , 10 - 20, and 5 - 1. To turn the awkward "10 - 20" into "20 - 20", add 10 to to get Now solve to get , then undo the rounding by subtracting 10 to get Multiplication : For 38 x 3 , you can add 2 to 38 to make the problem 40 x 3, which is Method 3 of Reorder the numbers to make convenient sums.

An addition problem is the same no matter what order you solve it in. Method 4 of Keep track of the hundreds, tens, and ones places. On paper, most people multiply the ones place first, going from right to left. Add them all together to get If both numbers have more than one digit, you can break it into parts. Each digit has to multiply with each other digit, so it can be tough to keep track of it all. Method 5 of Try this method of turning one hard problem into two easier ones.

This is another way of breaking a problem into parts. It can be a little tricky to remember at first, but once you have it down it can make multiplication much faster. This is easiest when multiplying two numbers that are both in the range of 11 to 19, but you can learn to use it for other problems: [2] X Research source Let's look at numbers close to 10, like 13 x Careful with smaller numbers!

If it's hard to work with negative numbers in your head, try a different method for problems like this. For larger numbers, it will be easier to use a "base number" like 20 or 30 instead of If you try this, make sure you use that number everywhere that 10 is used above. Method 6 of If the numbers end in zeroes, you can ignore them until the end: Addition : If all numbers have zeroes at the end, you can ignore the zeroes they have in common and restore them at the end.

Notice that you can only remove the two zeroes the numbers have in common, and must keep the third zero in Multiplication : ignore all the zeroes, then restore each one individually.

Division : you can remove all shared zeroes and the answer will be the same. Don't add any zeroes back on. Method 7 of You can convert these problems so they only use 2s and 10s. Here's how: To multiply by 5, instead multiply by 10, then divide by 2. To multiply by 4, instead double the number, then double it again. For 8, 16, 32, or even higher powers of two, just keep doubling.

Method 8 of You can multiply a two-digit number by 11 with barely any math. Add the two digits together, then put the result in between the original digits: [4] X Research source What is 7 2 x 11? The 2 goes in the middle and the 1 gets added to the 5 to make 6. Method 9 of Know which percentages are easier to calculate in your head. This is true of any two numbers.

If you can't find the answer to a percentage problem, try switching it around. Method 10 of These tricks are powerful, but narrow. They can turn a seemingly impossible mental math task into a quick task, but will only work on a very small percentage of problems. This also works for larger numbers if all digits besides the ones place are identical. Method 11 of Squares charts give you a new way to multiply. Memorizing your multiplication tables from 1 to 9 makes single-digit multiplication automatic.

But for larger numbers, instead of trying to memorize hundreds of answers, it's more efficient to memorize just the squares instead each number times itself. With a little extra work, you can use these squares to find the answer to other problems: [8] X Research source Memorize the squares from 1 to 20 or higher, if you're ambitious.

To multiply two numbers, first find their average the number exactly between them. For example, the average of 18 and 14 is Square this answer. Once you've memorized the squares chart, you'll know that 16 x 16 is Always use a positive number here.

Method 12 of Daily practice will make a huge difference. If you want to increase your confidence and speed at mental math, make an effort to use those skills at least two or three times a day. These suggestions can help you make this practice more effective: Flashcards are great for memorizing multiplication and division tables, or for getting used to tricks for specific kinds of problems.

Write the problem on one side and the answer on the other, and quiz yourself daily until you get them all right.