Saturday, 10 November 2012


Sneak some spelling into this math problem.
1.  Select any number. Write it out as a word; six hundred and six.
2.  Count the letters (but don’t count spaces or the hyphen); 13.
3.  Write down the number of letters as a word; thirteen.
4.  Count the letters in that word; 8.
Count the letters of that word; eight. The answer will always work down to “4.” So, 5 (letters in eight), five, 4!
Do this trick on a calculator with a 10-digit display or work it out on paper.
1.  Choose any number 1 through 9; 8.
2.  Multiply that number by the magic number – 123,456,789; 8 x 123456789 = 98,765,432
3.  Multiply the answer by 9; 98,765,432 x 9 = 8,888,888,808.
4.  The answer will be a 10-digit number, with nine of the digits the same as the number chosen in step 1.

The answer here will always work out to 1.
1.  Ask another person to choose a number from 1 to 10 without revealing this number; 3.
2.  Have them double the number; 3 + 3 = 6.
3.  Add 2 to the result; 6 + 2 = 8.
4.  Divide that number by 2; 8 divided by 2 = 4.
5.  Subtract the original number from the answer in step 4; 4 – 3 = 1.
6.  The answer is always 1.

It seems like magic that the answer always works out to 9.
1.  Enter into a calculator any number that consists solely of the number nine repeated; 9,999.
2.  Multiply it by any number; 9,999 x 25 = 249,975.
3.  Write down the number on paper.
4.  Add the individual digits in the answer; 2 + 4 + 9 + 9 + 7 + 5 = 36
5.  Add the answer digits together. If the answer isn’t 9, repeat adding the new answer digits until the result is 9

Friday, 9 November 2012



·       A math student is pestered by a classmate who wants to copy his homework assignment. The student hesitates, not only because he thinks it's wrong, but also because he doesn't want to be sanctioned for aiding and abetting.
His classmate calms him down: "Nobody will be able to trace my homework to you: I'll be changing the names of all the constants and variables: a to b, x to y, and so on."
Not quite convinced, but eager to be left alone, the student hands his completed assignment to the classmate for copying.
After the deadline, the student asks: "Did you really change the names of all the variables?"

·       Teacher: "Who can tell me what 7 times 6 is?"
Student: "It's 42!"
Teacher: "Very good! - And who can tell me what 6 times 7 is?"
Same student: "It's 24!"

·       Why do mathematicians, after a dinner at a Chinese restaurant, always insist on taking the leftovers home?
A: Because they know the Chinese remainder theorem

·       Teacher: What is  2 k + k?
Student: 3000!

·       Q: What do you get if you divide the cirucmference of a jack-o-lantern by its diameter?
A: Pumpkin Pi!

·       Q: Why do you rarely find mathematicians spending time at the beach?
A: Because they have sine and cosine to get a tan and don't need the sun!

·       Pi to i: Get real! 
i i to Pi Get rational!