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STUDY MATERIALS:

of the Date

Here are some shortcuts/tips to find out the day of the week from the given date. You can play these trick as instructed, with your parents or friends and prove your talent to them.

Day of the Week:
January has 31 days. It means that every date in February will be 3 days later than the same date in January(28 is 4 weeks exactly). The below table is calculated in such a way. Remember this table which will help you to calculate.

January	0
February	3
March	3
April	6
May	1
June	4
July	6
August	2
September	5
October	0
November	3
December	5

Step1: Ask for the Date. Ex: 23^rd June 1986
Step2: Number of the month on the list, June is 4.
Step3: Take the date of the month, that is 23
Step4: Take the last 2 digits of the year, that is 86.
Step5: Find out the number of leap years. Divide the last 2 digits of the year by 4, 86 divide by 4 is 21.
Step6: Now add all the 4 numbers: 4 + 23 + 86 + 21 = 134.
Step7: Divide 134 by 7 = 19 remainder 1.
The reminder tells you the day.

Sunday	0
Monday	1
Tuesday	2
Wednesday	3
Thursday	4
Friday	5
Saturday	6

Answer: Monday

Beauty of Mathematics:
    Here are some funny math interesting facts. All the below tricks are based around the sequential manipulation of the numbers being used for input and output.

Beauty of Mathematics

Sequential Inputs of numbers with 8 1 x 8 + 1 = 9 12 x 8 + 2 = 98 123 x 8 + 3 = 987 1234 x 8 + 4 = 9876 12345 x 8 + 5 = 98765 123456 x 8 + 6 = 987654 1234567 x 8 + 7 = 9876543 12345678 x 8 + 8 = 98765432 123456789 x 8 + 9 = 987654321 Sequential 1's with 9 1 x 9 + 2 = 11 12 x 9 + 3 = 111 123 x 9 + 4 = 1111 1234 x 9 + 5 = 11111 12345 x 9 + 6 = 111111 123456 x 9 + 7 = 1111111 1234567 x 9 + 8 = 11111111 12345678 x 9 + 9 = 111111111 123456789 x 9 + 10 = 1111111111 Sequential 8's with 9 9 x 9 + 7 = 88 98 x 9 + 6 = 888 987 x 9 + 5 = 8888 9876 x 9 + 4 = 88888 98765 x 9 + 3 = 888888 987654 x 9 + 2 = 8888888 9876543 x 9 + 1 = 88888888 98765432 x 9 + 0 = 888888888 Numeric Palindrome with 1's 1 x 1 = 1 11 x 11 = 121 111 x 111 = 12321 1111 x 1111 = 1234321 11111 x 11111 = 123454321 111111 x 111111 = 12345654321 1111111 x 1111111 = 1234567654321 11111111 x 11111111 = 123456787654321 111111111 x 111111111 = 12345678987654321 Without 8 12345679 x 9 = 111111111 12345679 x 18 = 222222222 12345679 x 27 = 333333333 12345679 x 36 = 444444444 12345679 x 45 = 555555555 12345679 x 54 = 666666666 12345679 x 63 = 777777777 12345679 x 72 = 888888888 12345679 x 81 = 999999999 Sequential Inputs of 9 9 x 9 = 81 99 x 99 = 9801 999 x 999 = 998001 9999 x 9999 = 99980001 99999 x 99999 = 9999800001 999999 x 999999 = 999998000001 9999999 x 9999999 = 99999980000001 99999999 x 99999999 = 9999999800000001 999999999 x 999999999 = 999999998000000001 ...................................... Sequential Inputs of 6 6 x 7 = 42 66 x 67 = 4422 666 x 667 = 444222 6666 x 6667 = 44442222 66666 x 66667 = 4444422222 666666 x 666667 = 444444222222 6666666 x 6666667 = 44444442222222 66666666 x 66666667 = 4444444422222222 666666666 x 666666667 = 444444444222222222 ......................................

Age Calculation

Here you can find the age using some tricks. You can play these trick as instructed, with your parents or friends and prove your talent to them.

Age Calculation

Age Calculation Tricks: Step1: Multiply the first number of the age by 5. (If <10 05.="" 5="" as="" consider="" ex="" if="" is="" it="">100, ex: 102, then take 10 as the first digit, 2 as the second one.) Step2: Add 3 to the result. Step3: Double the answer. Step4: Add the second digit of the number with the result. Step5: Subtract 6 from it.

Maths Trick 1

STEP 1
Ask a friend to write down a number (any number with more than 3 digits will do, but to save time and effort you might suggest a maximum of 8 digits).
Example: 83 972 105

STEP 2
Ask them to add the digits.
Example: 8+3+9+7+2+1+0+5 = 35      

STEP 3
Ask them to subtract this number from the original one.
Example: 83 972 105 – 35 = 83 972 070

STEP 4
Ask them to select any digit from this new number and strike it out, without showing you.
Example: 83 972 070      

STEP 5
Ask them to add the remaining digits and write down the answer they get.
Example: 8+3+9+7+0+7+0 = 34

STEP 6
Ask them to tell you the number they get (34) and you will tell them which number they struck out.

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SOLUTION
The way you do this is to subtract the number they give you from the next multiple of 9. The answer you get is the number they struck out.
Example: The next multiple of 9 here is 36 (9 x 4 =36)
36 – 34 = 2 and there you have your answer, easy isn’t it!

Note: If the number they give you after step 5 is a  multiple of 9, there are two possible answers  then you simply tell them that this time they crossed out either a 9 or a zero.

Maths Trick 2

Amazing 1089...

Step 1
Take two pieces of paper and hand one to a friend.
On yours, without letting them see, write the number 1089, then fold the paper to keep it hidden.
Step 2
Ask them to think of a 3-digit number but, before they write it down, ask them to put the numbers in order from greatest to smallest. Don't let them show what they've written.
Example: 543
Step 3
Below their number, ask them to write the same digits, but in reverse order, from smallest to greatest.
Example: 345
Step 4
Now, ask them to subtract the new lower number from the original one they wrote.
Example: 198
Step 5
Next, ask them to reverse the order of that number.
Example: 891
Step 6
Then, get them to add this latest number and the previous number together and show you the result.
Example: 891 + 198 = 1089
Step 7
Finally, you can reveal your own number, which (if they have calculated correctly) will be exactly what they have written...
1089

Maths Trick 3

Try this one in your head, using mental maths...

Step 1
Ask a friend to think of a number between 1 and 10.
Example: 8
Step 2
Get them to double it.
Example: 16
Step 3
Ask them to add 10 to the answer.
Example: 26
Step 4
Then get them to divide by 2.
Example: 13
Step 5
Ask them to tell you what number they now have.
Example: 13
Step 6
You subtract 5 from this and tell them what their original number was.
Example: 13 - 5 = 8
Note: If you wish to take turns to practice your mental maths, you can also use 2 and 3 digit numbers to make it harder!

Magic Squares

A magic square is a set of integers arranged in a square in such away that each row, each column (and often the two diagonals as well) sum to the same number.
For example: This 3 x 3 magic square's rows, columns and diagonals each add up to the number 15.

4	9	2
3	5	7
8	1	6

This 4 x 4 magic square's rows, columns and diagonals each add up to the number 34.

3	6	10	15
13	12	8	1
16	9	5	4
2	7	11	14

Squares

The result of squaring a number can also be arrived at by progressively adding consecutive odd numbers as shown below.

1²	= 1	= 1
2²	= 4	= 1+3
3²	= 9	= 1+3+5
4²	= 16	= 1+3+5+7
5²	= 25	= 1+3+5+7+9
6²	= 36	= 1+3+5+7+9+11
7²	= 49	= 1+3+5+7+9+11+13
8²	= 64	= 1+3+5+7+9+11+13+15
9²	= 81	= 1+3+5+7+9+11+13+15+17
10²	= 100	= 1+3+5+7+9+11+13+15+17+19

Did you know...

The Numbers 1 to 9

The sum of 1+2+3+4+5+6+7+8+9 = 45

Multiply 123456789 by 2 and you get 246913578,
the sum of which is 45
The "stations" of the nine times table all add up to nine.
9, 18, 27, 36, 45, 54, 63, 72, 81, 90