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Math trick

Math trick

Posers and Puzzles

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1. First of all, pick a number between 1 and 10.


2. Multiply this number by 2.


3. Add 5.


4. Multiply it by 50 - I'll wait while you get the calculator................


5. If you've already had your birthday this year add 1753.
If you haven't, add 1752.


6. Now subtract the four digit year that you were born.


You should have a three digit number.


The first digit of this is the one you started with.


The next two numbers are.....



YOUR AGE!

I think I;ve figured out how the age part gets worked into the result, but I'm still trying to figure out how your original number is worked in as well. I'll post tomorrow night what I've figured out and see if it matches any of your answers.

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1. First of all, pick a number between 1 and 10.
>n

2. Multiply this number by 2.
>2n

3. Add 5.
>2n+5

4. Multiply it by 50 - I'll wait while you get the calculator................
>100n+250

5. If you've already had your birthday this year add 1753.
If you haven't, add 1752.
>100n+2003

6. Now subtract the four digit year that you were born.
>100n+age

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Originally posted by Fiathahel
1. First of all, pick a number between 1 and 10.
>n

2. Multiply this number by 2.
>2n

3. Add 5.
>2n+5

4. Multiply it by 50 - I'll wait while you get the calculator................
>100n+250

5. If you've already had your birthday this year add 1753.
If you haven't, add 1752.
>100n+2003

6. Now subtract the four digit year that you were born.
>100n+age

You disappoint me with your incomplete explenation :-p In step 5 there are two possibilities...

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this does not work if your age is over 100!
i always heard this as "the number of times you want to dine out in a week (between one and ten)".
the "fudge factor" (1753 or 1752) is simply the current year minus 250 if you've had your birthday already or current year minus 251 if you haven't.
it thus will work for any year (until you become a centenarian) as long as you use the right fudge factor.
i used to know others like this; will see if i can find or recall them.

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try this.
1.)pick a multiple of 9, ex. 18 36
2.)add the two digits.
3.) subtract 5 from the number u get.
4.)Count in the alphabet how ever many numbers you got. ex 1=a, 2=b etc.
5.)pick a country that starts with the letter you got.
6.)pick an animal that starts with the second letter of the country you picked.

How many of you are riding an elephant in Denmark?

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Originally posted by TrollGirl28
try this.
1.)pick a multiple of 9, ex. 18 36
2.)add the two digits.
3.) subtract 5 from the number u get.
4.)Count in the alphabet how ever many numbers you got. ex 1=a, 2=b etc.
5.)pick a country that starts with the letter you got.
6.)pick an animal that starts with the second letter of the country you picked.

How many of you are riding an elephant in Denmark?
I am, but not from following those steps. *uncomfortable silence* Uh, so, yeah...

1 edit
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It doesn't work.

I wonder if you copied that from a two-year-old source...?

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Originally posted by TrollGirl28
try this.
1.)pick a multiple of 9, ex. 18 36
2.)add the two digits.
3.) subtract 5 from the number u get.
4.)Count in the alphabet how ever many numbers you got. ex 1=a, 2=b etc.
5.)pick a country that starts with the letter you got.
6.)pick an animal that starts with the second letter of the country you picked.

How many of you are riding an elephant in Denmark?
An alternate that takes it a little further.....

6) Pick an animal that starts with the last letter of the country you picked.
7) Pick a color that starts with the last letter of the animal you picked.

You should have an orange kangaroo in Denmark....

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Originally posted by Bowmann
It doesn't work.

I wonder if you copied that from a two-year-old source...?
Sorry!
My math teacher told us that a while ago and I guess I didn't do it right.

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Originally posted by TrollGirl28
Sorry!
My math teacher told us that a while ago and I guess I didn't do it right.
I meant the "trick" posted initially.

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Originally posted by TrollGirl28
try this.
1.)pick a multiple of 9, ex. 18 36
2.)add the two digits.
3.) subtract 5 from the number u get.
4.)Count in the alphabet how ever many numbers you got. ex 1=a, 2=b etc.
5.)pick a country that starts with the letter you got.
6.)pick an animal that starts with the second letter of the country you picked.

How many of you are riding an elephant in Denmark?
No. An emu in Djibouti.

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Originally posted by Bowmann
No. An emu in Djibouti.
Aha! Hoisted on your own petard. You should have been riding a jackalope in Djibouti. Or Katie B. from Jakalope, either one.

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Originally posted by PBE6
Aha! Hoisted on your own petard. You should have been riding a jackalope in Djibouti. Or Katie B. from Jakalope, either one.
You're quite right. Although I'm sure an emu would be easier.

On second thoughts, perhaps Katie B. would.

1 edit
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I'm riding an oryx in Morocco!

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Originally posted by Bowmann
You're quite right. Although I'm sure an emu would be easier.

On second thoughts, perhaps Katie B. would.
You can grab both by the ears, although one is cuter. I won't say which!
😲