@sweatlockjr : I think you need to read my post more carefully. First of all, he said he could make the measurement of 112.2 cm TO THE NEAREST TENTH CM--which is equivalent to saying a precision of measurement of +/- 0.05 cm. Accuracy is indeed +/- 0.04%. It's then accurate to add up whatever number of pieces you have, round to 4 sig figs, and then announce your number, with a measurement precision of 0.04% The 0.04% SHOULD BE INCLUDED, since he has TOLD US the measuring precision.
@sweatlockjr 112.2 represents anywhere between 112.15 to 112.25. From here the logic flows that his answer is not guaranteed, and therefore too specific.
Sal Khan's talent is not how much he knows, most high school teachers (at least in my country) know as much about sciences as him (well, maybe a little less than him). His real talent is how clearly he gets the point across so that the average listener with average IQ almost always understands what's being discussed. Good voice + neat mental organization/presentation + easy going personality + honesty = awesome teacher (that's Sal)
@junior1984able hehe actually, you would have all this knowledge too, if you went to Harvard and MIT like he did. all the subjects he's teaching is minimum requirements to even get into those Ivy League Universities, especially if you are majoring in a scientific, financial, engineering, computer related field which ofourse was his major.
Hmmm I'm not sure about this one. Since 112.2 CAN in theory be 112.24, you cannot with certainty say that that times 5 will be 561.0. I believe the correct answer would be 561 (with a significance range from 560.8 to 561.2).
Explained it better than any of my teachers. Thanks alot!
TheImHardkore 4 months ago
@sweatlockjr : I think you need to read my post more carefully. First of all, he said he could make the measurement of 112.2 cm TO THE NEAREST TENTH CM--which is equivalent to saying a precision of measurement of +/- 0.05 cm. Accuracy is indeed +/- 0.04%. It's then accurate to add up whatever number of pieces you have, round to 4 sig figs, and then announce your number, with a measurement precision of 0.04% The 0.04% SHOULD BE INCLUDED, since he has TOLD US the measuring precision.
GetMeThere1 6 months ago
@sweatlockjr 112.2 represents anywhere between 112.15 to 112.25. From here the logic flows that his answer is not guaranteed, and therefore too specific.
weckar 6 months ago
HOW MUCH KNOWLEDGE DO YOU THINK THAT ONE PERSON LIKE _______SAL KAHN COULD HAVE STORED PERMANENTLY IN HIS BRAIN?
junior1984able 10 months ago
Sal Khan's talent is not how much he knows, most high school teachers (at least in my country) know as much about sciences as him (well, maybe a little less than him). His real talent is how clearly he gets the point across so that the average listener with average IQ almost always understands what's being discussed. Good voice + neat mental organization/presentation + easy going personality + honesty = awesome teacher (that's Sal)
Byron10301 10 months ago 5
@junior1984able hehe actually, you would have all this knowledge too, if you went to Harvard and MIT like he did. all the subjects he's teaching is minimum requirements to even get into those Ivy League Universities, especially if you are majoring in a scientific, financial, engineering, computer related field which ofourse was his major.
EasternMerchant 7 months ago
@khanacademy Thanks for the vid
alexandrenr 10 months ago
Hey, how do significant figures apply to trigonometric, logarithmic, and exponential functions?
PaperSpock 10 months ago
SAL SAL, please do discrete math, like ya did Linear Algebra, a lot people would appreciate, Thank you for everything
Waranle 10 months ago
Hmmm I'm not sure about this one. Since 112.2 CAN in theory be 112.24, you cannot with certainty say that that times 5 will be 561.0. I believe the correct answer would be 561 (with a significance range from 560.8 to 561.2).
weckar 10 months ago
@weckar : 0.05/112.2 = about .04%. So you could write the answer: 561.0 +/- 0.04%.
That way, even if there were a million pieces, instead of only 5, the precision would still be +/- 0.04% of the number found to 4 sig figs.
GetMeThere1 10 months ago
@GetMeThere1 K thx, it confused me a bit!
weckar 10 months ago
I love to be the first one to comment.....I have nothing to say but I am in awe.
silencedidgood 10 months ago