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Some Lesser Known Tricks in Mathematics!

by Sep 11, 2016Mathematics

Mathematics is really a fascinating subject. A lot can be done with these numbers, magic tricks we call it sometimes. But the real trick lies with the numbers only.
Here is a list of such tips and tricks that you be amazed to know!

  1. The magic of the number 11.

When you have to multiply anything by 11, it is easy. This applies for any 2 digit number. What you have to do is, simply add the two numbers rather the two digits, and place them in between. That is the answer.
For example, suppose you are to multiply 54 with 11.
It is like 5_4
So, the sum of digits will be 5 + 4 = 9
594.
The final answer is 594.
But if the two numbers results a 2 digit result then simply place the first number in middle and add the 1 to the first number.
For example you are to multiply 93 with 11.
It is like 9_3
So, the sum of digits is 9 + 3 = 12
So
(9 + 1) 2 3
= 10 2 3
So the final answer is 1023.
It works all the time. Magic isn’t it!

  1. Quick Square of number ending with 5.

If you have to square a 2 digit number that ends with 5, then use can use this trick. You have to multiply the first digit with itself + 1 the number and simply put 25 in the end.
For example find the square of 25.
This will be 2 x (2+1) and 25
= 2 x 3 and 25
= 6 2 5.
So the answer is 625.
Again,
Consider to find the square of 35.
It is 3 x (3+1) and 25
= 3 x 4 and 25
= 1225
See!
Fantastic isn’t it?

  1. Leaving a descent tip so, finding proper percentage.

Suppose you require leaving a 15% tip, then check out this method.
Simply find the 10% of it (simply divide the bill amount by 10) and then add the number that is half of 10% of it.
For example if you have an amount says 300.
Divide it by 10 to find out its 10% which is 30.
So, half of its 10% is (10%of 300)/2 which is 15
So, it is 30 + 15
= 45.
Pretty simple. Isn’t it?

  1. Multiplication rules that make it simpler.

There are some pretty simple rules that exists making multiplication quite simple. Let’s look at those.

  • X 5. Multiplication by 10 is easy. Simply multiply by 10 and then divide by 2 to get proper answer for actual answer.

For example, 45 x 5 can be worked as
45 x 10 = 450
450 / 2 = 225
So answer is 225!

  • Multiply the number given to you originally by 10 and then subtract the number originally from the product obtained.

For example, 42 x 9 can be worked out as.
42 x 10 = 420
420 – 42 = 378
This way it can also be worked. It works for any number.

  • X 12. In order to multiply with 12, multiply with10 and then add twice the value of the original number with it to obtain the final answer.

For example, we have to perform 32 x 12.
32 x 10 = 320
32 x 2 = 64
And finally it becomes, 320 + 64 = 384
Nice isn’t it?

  • 4) X 13. Multiply the number with 10 and then add 3 times the original number to this product. For example, we have

25 x 13.
So 25 x 10 = 250
3 times 25 is 75
So, 250 + 75 = 325

  • 5) X 18. Simply multiply by 20 and then subtract twice the original number from product.

For example, you have to do 25 x 18. This can be worked as,
25 x 20 = 500
Then 500 – 50 = 450.
Simple!

  • X 19. Multiply the number with 20 and then subtract the original number in order to find the final result.

For example, 54 X 19 can be worked out as,
54 x 20 = 1080
1080 – 54 =   926
See?

  • X 45. Multiply the number by 50 and then subtract 5 times the original number to find final result.

For example, 32 x 45 can be easily worked out as,
32 x 50 = 1600
1600 – 160 = 1440

  • X 98. Multiplying by 98 is easy if you multiply the number with 100 and then subtract twice the original number, you can get the final answer.

For example, 23 x 98 can be worked out as,
23 x 100 = 2300
23 x 2 = 46
2300 – 46 = 2254
Pretty simple it is!

  • X 99. To multiply by 99 you have to multiply the number by 100 and simply deduct the original number from this product.

For example, 43 x 99 can be worked out as,
43 x 100 = 4300
4300 – 43 = 4257
4257 is the final answer.
Kids are taught from there nursery schools to deal with numbers. Care should be taken that easy tricks of calculation are not made available to small kids as it will greatly hamper their process of learning. These tricks as it is called should be made available at a proper and right age. Some students are found to enjoy mathematics while some are scared of them. But the most beneficial act for dealing with numbers is by Practicing. The more you practice, the better it gets for you. The techniques become all easy and you also remember it. Practice makes a man perfect, or if not perfect then close to perfect. Solve as many problems as you can get.
There is no short cut to success, so keep working hard.