Guest Posted November 16, 2007 Report Share Posted November 16, 2007 x=brick weight x=1+1/2x 1/2x=1 x=2kg Link to comment Share on other sites More sharing options...

Guest Posted December 14, 2007 Report Share Posted December 14, 2007 that is sssssssssssssooooooooooooooooooooooooooooooooooooooooooo stupid even my mom said so. netwebdave explanied it to me thanks Link to comment Share on other sites More sharing options...

Guest Posted December 17, 2007 Report Share Posted December 17, 2007 A brick weighs 2 Kg + 1/2 a brick. Therefore, 1/2 brick + 1/2 brick = 2 Kg, so 1/2 a brick weighs 1 Kg. Hence 3 half bricks must weigh 3 Kg. Alien1 Link to comment Share on other sites More sharing options...

Guest Posted December 17, 2007 Report Share Posted December 17, 2007 Sorry people, I was thinking in pounds, which would have been 3.3 pounds . The answer should be one and one half Kg. Link to comment Share on other sites More sharing options...

Guest Posted January 31, 2008 Report Share Posted January 31, 2008 This is my first visit to the site, and I've never posted before, but I found the discussion interesting and figured I'd throw my .02 in. An old riddle is as follows: One brick is one kilogram and half a brick heavy. What is the weight of one brick (previously: How heavy is one brick)? (This is a typical elementary math brain teaser.) I think the intent of the riddle is weight = mass, so we can throw all the weight vs. mass debates out the window, it just complicates things. If one follows the algebraic interpretation of this riddle, one would be inclined to assume that the equation would look like this: 1 brick = 1kg + .5 brick or 1x = 1kg + .5x so 1x - .5x = 1kg .5x = 1 kg x = 1kg/.5 x = 2kg the 2 kg answer is correct, but the wording of the riddle is slightly flawed and open to interpretation. If we look at the problem as parsimoniously as possible, which is likely what the riddle-maker intended, it yields a logical answer of 1 brick = 2kg. Link to comment Share on other sites More sharing options...

Guest Posted February 14, 2008 Report Share Posted February 14, 2008 (edited) Im in algebra 2 so if X = weight of the the brick the equation would be X=1kg+1/2 x Combine like terms using properties of equality if nessesary (subtaction property) X-1/2x=1kg+1/2x-1/2x Simplify (Substatution property) 1/2x=1kg Isolate variable 2*1/2x=1kg*2 SImplify x=2kg Answer the question The brick weighs 2 kg the weight has already been found so there is no need for any other formulas to solve the equation like the newtons thing and KG is a valid form of weight mesurment. That arguement is for another thread though Edited February 14, 2008 by Nabtalkin Link to comment Share on other sites More sharing options...

Guest Posted February 29, 2008 Report Share Posted February 29, 2008 Just thinking about the result after reading a lot of posts. Another way to think about the problem... purely using logic and not relying on math equations. The brick's total weight = 1kg + another 1/2 a brick. By this logic that means the other half of the brick must be the 1kg.. as there are no other weights in the problem. So if by process of elimination of weights 1kg has to = 1/2 a brick weight. Therefore 1 brick HAS to equal 2kg. Link to comment Share on other sites More sharing options...

Guest Posted March 3, 2008 Report Share Posted March 3, 2008 1 1/2 kilograms Link to comment Share on other sites More sharing options...

Guest Posted March 5, 2008 Report Share Posted March 5, 2008 well, 1 brick = 1kg + 1/2 brick how heavy is 1/2 a brick? 1/2 brick = 1/2kg + 1/4 brick how heavy is 1/4 brick? 1/4 brick = 1/4kg + 1/8 brick etc. etc. etc... so basically it becomes: 1 Brick = 1 + 1/2 + 1/4 + 1/8 + 1/16 + 1/32 +...+ and so on Conclusion[/b] even though when u solve for the equation you get: (brick = x) x = 1 + 1/2x x - 1/2x = 1 x(1-1/2) = 1 x = 1 / (1 - 1/2) x = 2 the real weight of 1 brick never really reaches 2. Instead, its 1.99999 > 2 (you can add as many 9s as u want...) Link to comment Share on other sites More sharing options...

Guest Posted March 6, 2008 Report Share Posted March 6, 2008 i get it now- x=1+1/2(x) Link to comment Share on other sites More sharing options...

Guest Posted April 7, 2008 Report Share Posted April 7, 2008 well, 1 brick = 1kg + 1/2 brick how heavy is 1/2 a brick? 1/2 brick = 1/2kg + 1/4 brick how heavy is 1/4 brick? 1/4 brick = 1/4kg + 1/8 brick etc. etc. etc... so basically it becomes: 1 Brick = 1 + 1/2 + 1/4 + 1/8 + 1/16 + 1/32 +...+ and so on Conclusion[/b] even though when u solve for the equation you get: (brick = x) x = 1 + 1/2x x - 1/2x = 1 x(1-1/2) = 1 x = 1 / (1 - 1/2) x = 2 the real weight of 1 brick never really reaches 2. Instead, its 1.99999 > 2 (you can add as many 9s as u want...) However, repeating 9999s after a decimal point = 1. Simple proof, .999 = x 10x = 9.9999999... - x = .99999... ------------------------ 9x = 9 x = 1 thus .999999... = 1 thus 2 is the correct answer Link to comment Share on other sites More sharing options...

Guest Posted April 18, 2008 Report Share Posted April 18, 2008 Call me dumb but i read it as 1 brick = 1.5kg Can sum1 show me an EASY WAY to solve this? x Link to comment Share on other sites More sharing options...

Guest Posted May 1, 2008 Report Share Posted May 1, 2008 Ok this is an elementary problem not college. In college you would take apart the wording to make sure you did not misunderstand. it said that a brick(1 brick) weights 1 Kg then that 1/2 a brick is heavy before asking the weight of the brick. It is one of those riddles that it gave you the answer in the beginning then handed you more filler information so that when it asked you to regurgitate the information back to it you are so confused you cannot answer properly. the answer is 1 kilogram Link to comment Share on other sites More sharing options...

Guest Posted May 4, 2008 Report Share Posted May 4, 2008 guys, this problem doesn't need to be so complicated. the wording may be funny, but the solution is all the same: first of all, a brick = one brick. what reason is there to distinguish the two? secondly, let 1 brick = n n = 1 kg + 1/2n n - 1/2n = 1 anything minus half of itself equals the other half, therefore: 1/2n = 1 n = 1 : 1/2 = 1 x 2/1 = 2 n = 2 kg Link to comment Share on other sites More sharing options...

Guest Posted May 4, 2008 Report Share Posted May 4, 2008 (edited) ok guys, 1 brick = 1kg + 1/2 brick so the 1kg is the only 1/2 if the brick so that means that the other half also = 1kg 1kg+1kg=2kg Edited May 4, 2008 by theshredder157 Link to comment Share on other sites More sharing options...

Guest Posted June 3, 2008 Report Share Posted June 3, 2008 I guess this depends on how you read the question. I read (1 brick is 1 kg) and (1 brick is half a brick heavy), not (1 brick is (1kg + half a brick) heavy). It's the difference between me reading "and" as a logical operator and you reading "and" as an arithmetic operator. Under my version, there are two options: 1. The term "brick" is ambiguous. You just said "one brick" weighs* 1 kg, so how can it also weigh 2 kg? If "one brick" is typical of "a brick" then the word problem is invalid: 1 brick = 1/2 brick 1 brick = 1 kg 1 kg = 1/2 * 1 kg 1 kg = 1/2 kg 1 = 1/2 Since 1 does not equal 1/2, 1 brick does not equal 1/2 brick and the problem is invalid. 2. If "one brick" is not typical of "a brick", then the problem changes: 1 [one brick] = 1/2 [a brick] 1 [one brick] = 1 kg 1 kg = 1/2 [a brick] 2 kg = [a brick] 1 [one brick] = 1/2 [a brick] 1 kg = 1/2 * 2 kg 1 kg = 1 kg 1 = 1 Since 1 does equal 1, this version is accurate, "one brick" weighs 1 kg and "a brick" weighs 2 kg. However, the question is not how much "a brick" weighs, but how much "one brick" weighs, so no math is necessary: "one brick" weighs 1 kg, as stated, and the answer is 1 kg, not 2 kg. As I read it, it's a very simple logic problem designed to confuse by seeming more complicated than it is. Under the other interpretation, your answer of 2 kg is valid, but it's not a logic problem anymore. * Technically, kg measures mass, not weight. So a valid answer on Earth would either be 2.2 lbs (the weight of 1 kg sitting on the surface of Earth) or 4.4 lbs (2 kg), depending on which interpretation we went with. Since you said "how heavy", not "what is the weight", this may be an inaccurate semantic argument, but is something I came up with under the logic realm. you really missed this one, I think you over-thought it LOL your premise to begin is invalid: 1 brick = 1/2 brick the problem stated" 1 brick = 1 kg + 1/2 brick be careful on your assumptions and keep on trying! otherwise your technical analysis is very well thought out Link to comment Share on other sites More sharing options...

Guest Posted June 29, 2008 Report Share Posted June 29, 2008 well, 1 brick = 1kg + 1/2 brick how heavy is 1/2 a brick? 1/2 brick = 1/2kg + 1/4 brick how heavy is 1/4 brick? 1/4 brick = 1/4kg + 1/8 brick etc. etc. etc... so basically it becomes: 1 Brick = 1 + 1/2 + 1/4 + 1/8 + 1/16 + 1/32 +...+ and so on Conclusion[/b] even though when u solve for the equation you get: (brick = x) x = 1 + 1/2x x - 1/2x = 1 x(1-1/2) = 1 x = 1 / (1 - 1/2) x = 2 the real weight of 1 brick never really reaches 2. Instead, its 1.99999 > 2 (you can add as many 9s as u want...) Well it actually does as that 1.99999.... = 2 check it out: let x=1.9repeated. then 10x = 19.9repeated subtract x = 1.9 from that and you get: 9x = 18 divide both by 9 x=2 Q.E.D. Link to comment Share on other sites More sharing options...

Guest Posted November 9, 2008 Report Share Posted November 9, 2008 Wow, i cant believe there's so many responses to such an easy problem... Ok ppl, I think the easiest way to go about solving this problem without any algebra or whatever else, is to simply use ur imagination. Sounds cheesy, but picture this: Picture a balance, on one side is one brick and on the other side is half a brick PLUS a KG of whatever the heck u'd like to imagine.... (rocks in a bag, eggs, whatever) Now, since the two sides must obviously balance out, since the problem stated this, you must know that the half-brick has to equal the kilo of whatever you have to balance with the other whole brick. Because its like having 2 halves of brick on one side and on the other the half brick plus something that weighs the SAME as half a brick (which is the 1kg). So the solution becomes very obvious once you picture that. I do have to admit, it was a bit confusing at first with the way it was worded, but a little bit of thinking and.... it was a piece of cake Link to comment Share on other sites More sharing options...

Guest Posted December 1, 2008 Report Share Posted December 1, 2008 1 brick equals 1 and 1 and a half kgs is the the answer because one brick =one kg and half a brick so half of a brick would be half a kg. right? Link to comment Share on other sites More sharing options...

Guest Posted March 19, 2009 Report Share Posted March 19, 2009 Problems like this always frustrated me in school because Like many people posting answers here I am too smart. What I mean is this riddle is valid but stated but in an ambiguous manner. You would never state the question like the original poster did because you recognize it as ambiguous. If you assume that the person asking the riddle is also smart enough to recognize that its ambiguous you then assume there must be something your missing. What the riddle should teach you is not some new mathematical equation but rather to look at problems differently. Often in life you are dealing with people who will not recognize their own ambiguity. So try to relax and realize that the simplest answer is usually the right one. Although I admit my very first thought was 1 brick = 1 kilogram but then I reread it and realized 1 brick = 1 kilogram and(+) 1/2 a brick that is natural and I believe the intent of the riddle. 1 brick = 2 kilograms Link to comment Share on other sites More sharing options...

Guest Posted March 19, 2009 Report Share Posted March 19, 2009 Brick - Back to the Logic Puzzles One brick is one kilogram and half a brick heavy. What is the weight of one brick? Brick - solution There is an easy equation which can help: 1 brick = 1 kg + 1/2 brick And so 1 brick is 2 kg heavy. An old riddle is as follows: One brick is one kilogram and half a brick heavy. What is the weight of one brick (previously: How heavy is one brick)? (This is a typical elementary math brain teaser.) I guess its a matter of perseption: The statement says one brick is heavier by 1kg and the weight of one brick. and the question is how much does 1 brick weight. So if one brick is heavier than the other then the following is true: 1st we have 2 bricks the first brick is of normal weight = X (unknown) the second is also unknown lets call it Y so: Y = X + (1kg + 1/2X) isolate X and theres your answer. it will be an equation not a solid number! Link to comment Share on other sites More sharing options...

Prof. Templeton Posted March 19, 2009 Report Share Posted March 19, 2009 I guess its a matter of perseption: The statement says one brick is heavier by 1kg and the weight of one brick. and the question is how much does 1 brick weight. So if one brick is heavier than the other then the following is true: 1st we have 2 bricks the first brick is of normal weight = X (unknown) the second is also unknown lets call it Y so: Y = X + (1kg + 1/2X) isolate X and theres your answer. it will be an equation not a solid number! I think the weight is uniform for all bricks, so there is only 1 unknown (the weight of the brick), not 2x = 1 + 1/2x 1/2x = 1 x = 2 Link to comment Share on other sites More sharing options...

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