BRAIN TEASERS
Brain Teasers User Profile

hung nguyen sy

rank
61
points
193
See full ranking list
short ranking list
59. ভাস্কৰ জ্যোতি 202
60. Dejan Radovanović 202
61. hung nguyen sy 193
62. Alyssa Wu 192
63. Victoria Ogino 191
last 3 solved tasks
MATH PUZZLE: Can you replace the question mark with a number?
The computer chose a secret code (sequence of 4 digits from 1 to 6). Your goal is to find that code. Black circles indicate the number of hits on the right spot. White circles indicate the number of hits on the wrong spot.
The computer chose a secret code (sequence of 4 digits from 1 to 6). Your goal is to find that code. Black circles indicate the number of hits on the right spot. White circles indicate the number of hits on the wrong spot.

Chester F. Carlson

Died 19 Sep 1968 at age 62 (born 8 Feb 1906). Chester Floyd Carlson was an American physicist who invented xerography (22 Oct 1938), an electrostatic dry-copying process that found applications ranging from office copying to reproducing out-of-print books. The process involved sensitizing a photoconductive surface to light by giving it an electrostatic charge Carlson developed it between 1934 and 1938, and initially described it as electrophotography It was immediately protected by Carlson with an impenetrable web of patents, though it was not until 1944 that he was able to obtain funding for further development. In 1947 he sold the commercial rights for his invention to the Haloid Company, a small manufacturer of photographic paper (which later became the Xerox Corporation).

Boss Issues

A boss was complaining in a staff meeting the other day that he wasn't getting any respect. Later that morning he went to a local sign shop and bought a small sign that read, "I'm the Boss". He then taped it to his office door.
Later that day when he returned from lunch, he found that someone had taped a note to the sign that said. "Your wife called, she wants her sign back!"

Jokes of the day - Daily updated jokes. New jokes every day.
Follow Brain Teasers on social networks
This site uses cookies to store information on your computer. Some are essential to help the site properly. Others give us insight into how the site is used and help us to optimize the user experience. See our privacy policy.