| Checksum Puzzle | How to make Silver Fulminate |
| Submitted On: Sunday, July 4, 2010 at 1:16:10 AM |
ColinFiat Please login to rate this submission. Link to this Submission Blog and Forum Link HTML link Facebook / Pagereaders
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DO NOT ATTEMPT: Articles provided here are for INFORMATIONAL PURPOSES ONLY. DO NOT undertake any project based upon any information obtained on the internet, including this website. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site. Please read the Legal page for more information.  It is quite simple to see that three 4 unit sticks are required to equal the length of a 12 unit stick. 3 x 4 = 12 Another way to express this is with cross multiplication. The question, for easier understanding, should be rephrased to: How many 12 unit sticks and how many 4 unit sticks are required to make a stick of 12 units. X * 4 = 12 Divide each side of the equation by 4: X * 4 = 12 4 = 4 Simplify by removing 4/4 and you have a simple X = 12 / 4 where the answer is 3. Three sticks of 4 units are required to equal one stick of 12 units. This time we need to change the length of the 12 unit stick and change the 4 unit stick by the same proportion. If we double the 12 unit stick then we need to also double the 4 unit stick. That’s obvious. But what if we changed the 12 unit stick to 18 units? How many units must the 4 unit stick measure to be proportional in size? 12 = 18 4 = X 12 units now equals 18 units the same as 4 units now equals X units. Let’s rewrite the equation by dividing both sides by 18 in order to leave X as an answer on its own. 12 = 18 4 * 18 = X * 18 Simplify by dividing out the two 18’s (18 / 18 = 1) 12 = 1 4 * 18 = X Ok, we’ve got a difficult equation (on purpose). So simply, flip each side of the equation to make life easier. (Try visualize it as 50/100 = 1/2 or 50/100 = half. That’s the same as 100/50 = 2/1 when flipped.) 4 * 18 = X 12 = 1 4 * 18 / 12 = 6 To maintain proportionality when a 12 unit stick is increased to 18 units, a 4 unit stick must be increased to 6 units. Let’s test this by working out how many 6 unit sticks are required to equal the new 18 unit stick. 3 x 6 = 18; the same number as before. So much for sticks. Let’s move onto 2 dimensional objects. You have a wide screen movie and wish to convert it to TV standard without loss of image ratio – you don’t want a tall thin movie and you also don’t want to cut off either the left or right of the picture.  To reduce the width of the green wide screen to the blue standard screen width and maintain a normal shaped image, the height must also be changed maintaining the width/height ratio. 640 = X 720 = 320 Now we cross multiply but this time I’ve shown it in an easier to manipulate manner where the 320 is simply moved up and across; essentially multiplying both sides by 320. (To describe this; a square with width and height of 720 by 320 is resized to a width and height of 640 by what?) 640 * 320 / 720 = X = 284 Taking the opposite action, increasing the height of wide screen 720x320 to stan...
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| Tags: resize, image, multiply, ratio, aspect |
| Tuesday, July 6th, 2010 at 6:33:21 AM #46337 |
 Toasty SysOp Level 40 Posts: 7,353 Submissions: 227  | I skimmed it, seems interesting. When I'm out of work today I'll read through it better. Already 5'd it though. |
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| Thursday, March 31st, 2011 at 4:11:55 PM #52707 |
 timmydogman Member 'Senator The Long' Level 13 Posts: 453 Submissions: 21 | 5* |
| Wednesday, August 3rd, 2011 at 4:19:17 AM #53667 |
 Makenshi Member Level 1 Posts: 36 Submissions: 1 | I have a flash video about weird math like this. How one 8 by 8 square can be cut to create a 13 x 5 rectangle. It quite confused me lol. Here's a link to the puzzle, however its not the animated one I have. Also thought the triangle was quite interesting. http://www.jimloy.com/puzz/missing.htm |
