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DCI Matte Black Powder Coated Metal Mathematics Blackboard Pop Quiz Clock, 11-1/2" Diameter
|Price:||$29.99 & FREE Shipping on orders over $35. Details|
|You Save:||$2.00 (6%)|
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- Enter your model number above to make sure this fits.
- Each hour is marked by a simple math problem
- Matte black powder coated metal
- Requires 1 AA battery
- 11-1/2" Diameter
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CHOKING HAZARD -- Small parts. Not for children under 3 yrs.
Top Customer Reviews
***Update*** 4/1/2013 SO i did a little tinkering because I was bored on saturday and had nothing better to do... Turns out this whole thing is an undersized gear problem for the second hand... The gear is just way to small for the size and weight distribution of the second hand... So a simple fix for this, if your clock does what mine did, is to simple trim down the second hand to a size of abotu 3 inches from the base point tot he tip. Seems to be working just fine now. Still only going to give it two stars, as I had to take it apart to make it work
It's a great novelty item, everyone notices it and gets a kick out of it.
The circle that makes up the face is a thin piece, mounted on the square that houses the battery and mechanical parts behind it, so the circle will not sit flush on a wall. And the mount is in the middle of the top of that smaller square in back, making it tougher to find the right hanging point for mounting it.
Other than that, it works well, keeps pretty good time actually, only has to be adjusted a couple minutes each month.
On quiet nights though when I'm just working on my laptop and nothing is on the TV, you can hear the tick tick tick though, so if you're a person who doesn't like the ticking noise, you won't want this hanging anywhere that gets quiet.
Now, on to the one problem with it. The expression that is supposed to evaluate to 9, which is 3 * (pi - 0.14), actually evaluates to around 9.00477. Pi is irrational, so you can't express a natural number like 9 with an expression containing pi. I'm sure this has driven many other mathematicians insane, and I seem to be the first one to speak up about it.
Other than that slightly anal comment, its a great clock!
Most Recent Customer Reviews
Great item, great price, good packaging. It hangs in a market research firm firms with quant, state and math folks.Published 4 days ago by Leather1905
I bought this as a gift to my brother. When it arrived I was a little bit disappointed. It looks cheaply made. The pictures were a little bit deceiving.Published 12 days ago by Romelpis1212
This was a graduation present and lasted two weeks when it literally lost parts and it never worked again.Published 15 days ago by gem
This clock is perfect for classrooms/faculty offices. I have had several students puzzling out the math to check if they are correct. Read morePublished 2 months ago by CJL