wolfgang Posted March 11, 2011 Report Share Posted March 11, 2011 If you have an unlimited amount of suger,One standared 5 kilos wieght,and a balance scale. I want you to weigh exactly 7 kilos suger using the balance scale ONLY. you can use it as much as you want! Any other method is NOT allowed. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 13, 2011 Report Share Posted March 13, 2011 Wolfgang's hint made me think... weighing 5kg of the sugar, counting the crystals, and adding another two-fifths. Of course, you would probably need tweezers to do that, and it would take forever, but it would work with very good accuracy. that's insane! Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 14, 2011 Report Share Posted March 14, 2011 Wolfgang's hint made me think... weighing 5kg of the sugar, counting the crystals, and adding another two-fifths. Of course, you would probably need tweezers to do that, and it would take forever, but it would work with very good accuracy. I actually thought that but rejected it for it's clearly irrealistic. But you made me think you could just use sugar cubes Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 14, 2011 Report Share Posted March 14, 2011 (edited) I actually thought that but rejected it for it's clearly irrealistic. But you made me think you could just use sugar cubes I had similar idea since sugar is usuallu baged in one kilo bags or it comes in cubes. I hope it's not that or else I'm comming to Vienna to kick some a**! Edited March 14, 2011 by Ctpubop Quote Link to comment Share on other sites More sharing options...
0 wolfgang Posted March 14, 2011 Author Report Share Posted March 14, 2011 I actually thought that but rejected it for it's clearly irrealistic. But you made me think you could just use sugar cubes yes...thats it....super! Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 14, 2011 Report Share Posted March 14, 2011 Ahh, good one. ;-) Quote Link to comment Share on other sites More sharing options...
0 wolfgang Posted March 15, 2011 Author Report Share Posted March 15, 2011 I was joking....No its not the correct answer that I was looking for. I like suger thats why I made such a joke....sorry... No matter which powder is given,,,you should be able to weigh the 7 kilos(exactly!!). Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 17, 2011 Report Share Posted March 17, 2011 I was joking....No its not the correct answer that I was looking for. I like suger thats why I made such a joke....sorry... No matter which powder is given,,,you should be able to weigh the 7 kilos(exactly!!). I'm not in love with my solution, but I think this works. I'm going to assume a few things. The pans are big enough to hold very large amounts of sugar. And I have some extra containers to hold sugar I have weighed and accumulated. But, I will stay true to the problem, and do all my weighing strictly on the balance scale. The first thing to do is put the 5 kilo weight on one side and 5 kilos of sugar on the other side. Once I have a good idea of how much sugar 5 kilos looks like, I'll eyeball what I think 2 kilos of sugar is and place it with the 5 kilo weight. I will then assume I'm close and proceed to use what I think is 7 kilos (5 kilo weight and 2 kilos of sugar) to weigh 7 kilos of sugar 5 times, accumulating close to 35 kilos of sugar. Each 7 kilo batch gets collected in a single container. Then I will put the approximately 2 kilos of sugar in a separate container leaving the 5 kilo weight on the scale. I then proceed to weigh 5 kilos of sugar 7 times, putting each 5 kilo batch of sugar in a third container. I will now have a container that should have nearly 35 kilos of sugar in it, a container that has exactly 35 kilos in it, and a container with nearly 2 kilos of sugar in it. I will then weigh the two batches of 35 kilos against each other. The result of that weighing will determine my next move. If the batch I created 7 kilos at a time is a little heavier, I'll take away a little from the 2 kilo batch. If it's a little light, I'll add a little to the 2 kilo batch. I'll then discard the 35 kilo batch I created 7 kilos at a time, and place my slightly adjusted 2 kilo batch along with the 5 kilo weight back on the scale and create 5 more 7 kilo batches and again weight against the 35 kilo batch I saved (which I know is exactly 35 kilos). I will continue this process, honing in on the perfect 2 kilo batch, until my two 35 kilo batches weigh exactly the same. Once that happens, I will now know my 2 kilo batch is perfect. So, I would then place the perfect 2 kilo batch along with the 5 kilo weight on one side, and then weigh a perfect 7 kilo batch of sugar on the other side and I'm done. This solution is far from elegant, but with patience and plenty of time, it will work. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 17, 2011 Report Share Posted March 17, 2011 I was joking....No its not the correct answer that I was looking for. I like suger thats why I made such a joke....sorry... No matter which powder is given,,,you should be able to weigh the 7 kilos(exactly!!). Alright, but why did you say that if it was flour we couldn't measure it??? Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 17, 2011 Report Share Posted March 17, 2011 we have been thinking of the weighing scale, purely in its ability to weight out an equal amount of weight. What if we thought of it as a lever, with the center pivot as moveable. This way, we can include an addition variable into the question, and not be trapped by the cycle of + - / *. Firstly, we measure the entire length of the lever. Let the length be 1.2 m for ease of calculation. we then proceed to place the 5kg weight on end. We then position the pivot exactly 70cm from the 5kg weight. Following which we would add enough sugar for the weighting scale to be balanced. Following the physic formula for calculation on momentum, for the weighting scale to be balanaced, both clockwise and anticlockwise momentum has to be the same. In the sense that ml = ML (where m = 5kg, l = 70cm, L = 50cm and M = the required 7kg)/ Quote Link to comment Share on other sites More sharing options...
0 wolfgang Posted March 17, 2011 Author Report Share Posted March 17, 2011 (edited) Alright, but why did you say that if it was flour we couldn't measure it??? cause it is white... .that was only a joke...not more... now I am very serious.no kidding more... It has nothing to do with powder to be used,you can use sand also. Edited March 17, 2011 by wolfgang Quote Link to comment Share on other sites More sharing options...
0 wolfgang Posted March 17, 2011 Author Report Share Posted March 17, 2011 we have been thinking of the weighing scale, purely in its ability to weight out an equal amount of weight. What if we thought of it as a lever, with the center pivot as moveable. This way, we can include an addition variable into the question, and not be trapped by the cycle of + - / *. Firstly, we measure the entire length of the lever. Let the length be 1.2 m for ease of calculation. we then proceed to place the 5kg weight on end. We then position the pivot exactly 70cm from the 5kg weight. Following which we would add enough sugar for the weighting scale to be balanced. Following the physic formula for calculation on momentum, for the weighting scale to be balanaced, both clockwise and anticlockwise momentum has to be the same. In the sense that ml = ML (where m = 5kg, l = 70cm, L = 50cm and M = the required 7kg)/ Perfect!!! and thats the correct answer....congratulations Swongy Quote Link to comment Share on other sites More sharing options...
0 benjer3 Posted March 17, 2011 Report Share Posted March 17, 2011 (edited) we have been thinking of the weighing scale, purely in its ability to weight out an equal amount of weight. What if we thought of it as a lever, with the center pivot as moveable. This way, we can include an addition variable into the question, and not be trapped by the cycle of + - / *. Firstly, we measure the entire length of the lever. Let the length be 1.2 m for ease of calculation. we then proceed to place the 5kg weight on end. We then position the pivot exactly 70cm from the 5kg weight. Following which we would add enough sugar for the weighting scale to be balanced. Following the physic formula for calculation on momentum, for the weighting scale to be balanaced, both clockwise and anticlockwise momentum has to be the same. In the sense that ml = ML (where m = 5kg, l = 70cm, L = 50cm and M = the required 7kg)/ I thought we could only use the sugar, the scale, and the weight? I thought about this kind of thing, but we have no ruler. Edited March 17, 2011 by benjer3 Quote Link to comment Share on other sites More sharing options...
Question
wolfgang
If you have an unlimited amount of suger,One standared 5 kilos wieght,and a balance scale.
I want you to weigh exactly 7 kilos suger using the balance scale ONLY.
you can use it as much as you want!
Any other method is NOT allowed.
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