MemoryMentor’s Blog

Explain that you can adjust even large numbers quickly, so that they’re evenly divisible by a chosen number from 1-10.

First, you ask for a number from 1-10. Then, someone from your audience is asked to create a large random number (about 15-20 digits long). You take a brief glance at the number, make some minor adjustments to it, and declare it is now even divisible by the chosen number. Checking with a calcaultor, you are proven absolutely correct!

How is this done?

There are actually two tricks involved here. One is used if they chose 7, and the other is used if they choose any other number from 1-10.

If 7 is chosen:

Have them write down 9 random digits, and then have them write down the same 9 digits immediately to the right, but they don’t have to be in the same order as the first 9. For example, if the person writes:

406384514

…then they would write the same digits again next to it, but in a jumbled order, we might get this 18-digit number:

406384514143046854

Emphasizing there is no way you could have known that this would be the number generated, you take a quick glance at the number, ponder (for effect), and then look down and change the 2nd and the 11th numbers to a 7. In our example, the number would now read:

476384514173046854

The number is now evenly divisible by 7!

By generating the number as desribed above, and replacing the 2nd and 11th digits with a 7, you will ALWAYS get a multiple of 7!

If possible, have the person use a number that means something to them, like a phone number, to generate the first 9 digits. In the US, you can have them use their 9 digit “Social Security” number.

If any number except 7 is chosen:

In this case a 16-digit (not an 18-digit) number is created, and there is a little more freedom.

Have the person create a random 16 digit number (any 16-digit number will do).

Again, they should use a handy number, such as their phone number, from which to obtain the digits. In the US, the paper currency always has an 8-digit serial number on it, so you could have the person take out two bills, and copy the serial numbers next to each other.

As an example, let’s use the following 16-digit number:

9521531677651471

From here, there are two ways to go to make this 16-digit number divisible by the chosen number:

If the chosen number is 1, 2, 4, 5, 8 or 10:

Simply add “6240″ to the end of the number. It is now divisble by 1, 2, 4, 5, 8 and 10 (although you only emphasize the number they chose)! In our example, this would now look like:

95215316776514716240

Actually, just adding 240 to the end would also do it, but adding 4 digits makes it look like it took more thought!

If the chosen number is 3, 6 or 9:
You’ll need to figure the “digital root”. To get the digital root, you take the number add its digits, then adding the digits of numbers derived from it, etc., until the remaining number has only one digit.

In our example, we would add:

9+5+2+1+5+3+1+6+7+7+6+5+1+4+7+1

to get:

70

We then add 7+0 to get the number’s digital root: 7

If the digital root is even (0, 2, 4, 6, 8 ), then you subtract the number from 18, and append that number to the right of the 16-digit number.

If the digital root is odd (1, 3, 5, 7, 9), then you subtract the number from 9, and append that number to the right of the 16-digit number.

Remember: Even numbers are subtracted from 18, (the first even multiple of 9), and the odd numbers are subtract from 9 (an odd number).

The above rules insure that the resulting number will be divisible by 3, 6 AND 9.

In our example, the digital root is 7, so it’s odd. We subtract that from 9 (since it is odd), resulting in 2. So, we append a 2 to the right of the number, giving us:

95215316776514712

You can now confidently say that this number is divisible by the chosen number (if it were 3, 6 or 9).

I know this seems like a lot of work, but with a little practice, you can get the whole routine to flow quite smoothly.

Tips for remembering the redox reaction involving electrons:
LEO the lion goes GER
LEO - Loses electrons, oxidation
GER - Gains electrons, reduction

Another way: Remembering OIL RIG helps to define the redox reaction.

OIL = Oxidation Is Loss
RIG = Reduction Is Gain 

A little mnemonic here to help you remember the rankings in the US Military:

Be My Little General

B = Brigadier General (one star)
M = Major General (two stars)
L = Lieutenant General (three stars)
G = General (four stars)

Finding the square of a 2-digit number beginning with 1

1. Take a 2-digit number beginning with 1(e.g., 11 to19).
2. Square the second digit (keep the carry if any)
3. Multiply the second digit by 2 and add the carry from step 2(keep the carry from this step if any)
4. The first digit is one (plus the carry from step 3)

Example:
Find the square of 13
Take the second digit and square it = 3*3=9(no carry)
_ _ 9
Multiply the second digit by 2(3*2) = 6
_ 6 9
The first digit is one 169

Find the square of 19
Take the second digit and square it = 9*9 = 81
_ _ 1(carry
Multiply the second digit by 2 and add the carry (9*2)+8 = 18+8 = 26
_ 6 1 (carry 2)
The first digit is one (plus carry) = 1+2 = 3 361

Finding the square of a number made up of threes

Choose a number made up of threes.

1. Add 1 n-1 times (where n is the number of 3’s)
2. Add a zero
3. Add 8 n-1 times (where n is the number of 3’s)
4. Add a nine

E.g. Find the square of 333

1. Since we need to find the square of 333(which has three 3’s, n=3)
2. Add 1 n-1 times (3-1 =2) 11
3. Add a zero 110
4. Add 8 n-1 times (2 times) 11088
5. Add a nine 110889

Find the square of 3333333
1. n=7 ( as the number has 7 3’s)
2. Add 1 n-1 times (7-1 =6) 111111
3. Add a zero 1111110
4. Add 8 n-1 times (6 times) 1111110888888
5. Add a nine 11111108888889

Multiplying two 2 digit numbers where the first digit is the same and the sum of second digits is 10

1. Take two 2 digit numbers which has the same first digit and sum of second digits is 10
2. Multiply the second digits together
3. Multiply the first digit with its next number ( n* (n+1))

For e.g., 42*48

1. The first digit is the same and sum of the second digit adds to 10(2+8)
2. Multiple second digits 2* 8 = 16
_ _ 16
3. Multiply the first digit with its next number 4*5 = 20
2016

Bold Boys Ravage Only Young Girls But Violet Gives Willingly

Black Brown Red Orange Yellow Green Blue Violet Grey White

How to remember which resistor has the value of 0, Black always reminds me of black holes, where nothing can escape, so this makes me think of 0!

Therefore, the rest of the colours have the code 1,2,3,4,5,6,7,8 and 9 being white!

I have always wondered which way these go, is longitude North/South or East/West?

Well here is a nice easy way to remember which one is which.

Think of a ladder as it sounds like latitude.

The rungs of the ladder are horizontal, going from left to right, or east to west.

When you hear latitude you will think of ladder, then the rungs of the ladder. East/west, so latitude is horizontal. Therefore longitude is North/South or vertical!

Another method for memorizing longitude and latitude:
longitude has an N in it for North, so the north-south line is longtitude,
so the other east-west is latitude

The Knight’s tour is a great feat of mathematics that allow you to move the Knight around a chess board landing on all squares only once.
To see just how difficult it is, get out your chess board and try moving the Knight around the chess board in its L shaped motion. Imagine now that you were told to start on a particular square and do the tour from there. Or, you were told to finish on a particular square. The task will prove even more complicated!

There is a way to do the Knight’s tour starting on a given square or ending on a said square.
You will nee to have completed the Dominic System here
and you will be using numbers 1 though to 64 as there are 64 squares on a chess board.
The numbers you will need to memorize and the order they are in is below:

01, 11, 05, 20, 37, 27, 44, 29, 35, 50, 33, 43, 58, 41, 26, 09, 03, 13, 23, 08,
14, 04, 10, 25, 19, 02, 17, 34, 49, 59, 53, 47, 64, 54, 60, 45, 28, 38, 21, 36,
30, 15, 32, 22, 07, 24, 39, 56, 62, 52, 42, 57, 51, 61, 55, 40, 46, 63, 48, 31,
16, 06, 12, 18
In a situation like this it is possible to place four people from the Dominic System at each location. So in my first room, I have 01, 11, 05, and 20. But I don’t have four people in that room. I have two people. What I have is the first person, ie 01 (Ozzie Ardillez) doing the action of 11 Arthur Askey. So I use the image of a Bee for Arthur Askey so instead of Ozzie Ardillez kicking a football I imagine him doing kick ups with bees! You could imagine something different for example Ozzie could be running around waving his arms frantically in the air trying to get the bees away from him! Remember, whatever image comes to mind, use it. That is the image that will first come to you. Trust your imagination.

If you look at the bottom left corner (the black square), in chess, this is called A1. But we are going to call it 1. The bottom right square (white), is number eight.

I hope the picture is clear enough for you! Just start in the bottom left and you will be able to figure out which square is numbered with what.
So if you look at the list again, you can see, for example, 01, 11, 05, and 20 this is the route you take on the board. So 01 will be Ozzie Ardilez, square one, next route on the Knight’s tour, is 11, Arthur Askey. So if someone was to say to you to start from square E6, that would be square number 45. That would be Duke Ellington or whoever you have for number 45. You now know the next square will be 28, Benny Hill!

The Knight’s tour is a great feat of mathematics that allow you to move the Knight around a chess board landing on all squares only once.
To see just how difficult it is, get out your chess board and try moving the Knight around the chess board in its L shaped motion. Imagine now that you were told to start on a particular square and do the tour from there. Or, you were told to finish on a particular square. The task will prove even more complicated!

There is a way to do the Knight’s tour starting on a given square or ending on a said square.
You will nee to have completed the Dominic System here
and you will be using numbers 1 though to 64 as there are 64 squares on a chess board.
The numbers you will need to memorize and the order they are in is below:

01, 11, 05, 20, 37, 27, 44, 29, 35, 50, 33, 43, 58, 41, 26, 09, 03, 13, 23, 08,
14, 04, 10, 25, 19, 02, 17, 34, 49, 59, 53, 47, 64, 54, 60, 45, 28, 38, 21, 36,
30, 15, 32, 22, 07, 24, 39, 56, 62, 52, 42, 57, 51, 61, 55, 40, 46, 63, 48, 31,
16, 06, 12, 18
In a situation like this it is possible to place four people from the Dominic System at each location. So in my first room, I have 01, 11, 05, and 20. But I don’t have four people in that room. I have two people. What I have is the first person, ie 01 (Ozzie Ardillez) doing the action of 11 Arthur Askey. So I use the image of a Bee for Arthur Askey so instead of Ozzie Ardillez kicking a football I imagine him doing kick ups with bees! You could imagine something different for example Ozzie could be running around waving his arms frantically in the air trying to get the bees away from him! Remember, whatever image comes to mind, use it. That is the image that will first come to you. Trust your imagination.

If you look at the bottom left corner (the black square), in chess, this is called A1. But we are going to call it 1. The bottom right square (white), is number eight.

I hope the picture is clear enough for you! Just start in the bottom left and you will be able to figure out which square is numbered with what.
So if you look at the list again, you can see, for example, 01, 11, 05, and 20 this is the route you take on the board. So 01 will be Ozzie Ardilez, square one, next route on the Knight’s tour, is 11, Arthur Askey. So if someone was to say to you to start from square E6, that would be square number 45. That would be Duke Ellington or whoever you have for number 45. You now know the next square will be 28, Benny Hill!