Multiplication by 11

We all know that it is easy to multiply a single digit number by 11. If you want to multiply 4 by 11, you simply repeat the digit for the answer, 44. If you multiply 6 by 11, you get 66.
Did you know it is easy to multiply two digit number by 11?
Multiplying a two-digit number by 11.
To multiply 16 by 11, add both the digits of the given number, 1+6 = 7. Now place this answer , 7, in between the two digits, in this case giving you 176.
16 X 11 = 176
These calculations are easy to do in your head. If somebody asks you to multiply 52 by 11, you could immediately say, "five hundred and seventy two".
That was easy! Now, what happens if the digits add to ten or more? comments

Finding age trick

Math tricks are a lot of fun. Students love them in the classroom. We are more open to learning when we are having fun in the process. Math teachers often use number tricks in the classroom to encourage enthusiasm among students. You can use some of these tricks with your friends as well.

A simple trick to find someone's age.
Step 1) Ask your friend to multiply the first number of his age by 5.
Step 2) Now ask him to add 3 to the result.
Step 3) Tell him to double this figure.
Step 4) Finally, ask him to add the second number of his age to the resulting figure and have him tell you the answer.
Step 5) Now you deduct 6 from the answer and you will have his age.

I am sure your friends will be impressed. comments

Number Trick

An interesting trick of number 421. What is so special about the number 421?
Number 421 is the smallest prime number formed by the powers of two in logical order from right to left.

Follow the given steps and you will notice an interesting loop of 4...2...1...
1) Select any whole number.
2) If it is an even number,divide by 2; If it is an odd number, multiply by 3 and add 1 to it.
3) Keep on repeating the process mentioned in step 2. We'll see that after a while the value 4,2,1 repeats itself.

Example: Lets pick a number, say, 23.

23 is an odd number; so multiply by 3 and add 1 to it;
(23 × 3) + 1 = 70
70 is an even number; so divide by 2;
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Funny Calculations

You can play this funny Math trick with your friends. Ask them to do the following calculations and you can predict their date of birth.
1) Add 18 to your Birth month.
2) Multiply by 25.
3) Subtract 333.
4) Multiply by 8.
5) Subtract 554.
6) Divide by 2.
7) Add your Birth date.
8) Multiply by 5.
9) Add 692.
10) Multiply by 20.
11) Add only the last two digits of your Birth year.
12) Subtract 32940 to get your complete date of birth.

Suppose the answer is 102382. This implies that your friend's date of birth is October 23, 1982 (MM/DD/YY).
(Note: If the answer is not right, your friend did not follow the directions correctly or lied about his Birthday.) comments

Fibonacci Numbers

The numbers in the following integer sequence are called the Fibonacci numbers.
0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144…
By definition, the first two numbers in the Fibonacci sequence are 0 and 1, and each subsequent number is the sum of the previous two.
1 = 1+0
2 = 1+1
3 = 2+1
5 = 3+2
8 = 5+3
13= 8+5
21= 13+8
34= 21+13
55= 34+21

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