How accurate is the 'Rule of 70'?
116560
For those of you not familiar with the rule of 70, it goes something like this:  If you invest your money at X percent, it will take 70/x years to double.\n\nHere is why it works. Suppose that x = X/100 (10% is really .10 = 10/100)\n\nIf you start with a principle amount of P and invest it at rate X, after n years you have P(1+x)^n\n\nYou want to solve for P(1+x)^n = 2P or  (1+x)^n = 2.\n\nTake ln of both sides you get ln((1+x)^n) = ln2\n\nnln(1+x) = ln2\n\nln(1+x) = ln2/n\n\nThe Taylor series for ln(1+x) is x - x^2/2 + x^3/3 - x^4/4 + ...\nFor small values of x, ln(1+x ~ x\n\nso x ~ ln2/n, and X ~ 100ln2/n.\n\nln2 = .6931... so  X ~ 69/n and n ~ 69/X\n\nTo see how accurate it is, you have to look at the size of - x^2/2 + x^3/3 - ... which is relatively small since you are generally talking about values of x < .1\n\nI think the reason for Rule of 72 is that 72 is divisible by 2,3,4,6,8, and 12.
240093
English machine yeah? Everyone's different, for some their ideal reading is between 4 and 7, or for others it might be between 7 and 9. You need to find out what your ideal reading is.
55914
It must be very close to 100% :-)\nKind reg. from Europe
377806
If you are talking about average  blood sugar.. 80 to 120 is considered average, or "good".
990215
3.0 is a B so it would be a very high C. Unless they round them off these days in which case it would be a B.
907986
Seventy  percent (70%)
50952
like any physical parameter derived from measurement, results should be reported with a +/- experimental uncertainty.  unfortunately when these numbers are repeated in the media, rarely do they get repeated.  (and in fact, often scientists neglect to even publish them.  jerks.)\n\nanyway, a typical error bar for radiocarbon dating seems to be anywhere from 30-50 years.  so you can consider it accurate to within that margin of uncertainty.  however, depending on the data, sometimes this can increase to an error margin of several centuries!  (see 2nd link)
620327
150 is a good round number to go with.  Anything over 120 is considered high but your never no if you are level or moving up or down.  If you recently ate a meal and took insulin give it a chance to kick in and check again in 20 mins to see where you are headed up or down.
500584
Depending on the institution 70-110 or 80-120 is normal.  If it is just a little over, keep an eye on it, but yeah, consistently higher than that, you need to see your doc.
836107
Any number greater than 1.4 is correct.
1149812
that could be roughly true\nit depends on what is your heart rate (which as a matter of fact varies a lot through the day, and at different ages it varies too) and how long you live\nFor example babies have heart rates of 120 to 140 beats per minute while adult range from 60 to 100 \n\nIn the hypothetical case that the heart rate was kept constant through your entire life lets say at 60 (To take the lower end) and that you would live exactly 70 years that would be \n\n60 beats per minute times 60 minutes = 3600 in an hour\n3600 beats in an hour times 24 hours in a day = 86400 beats in a day\n86400 beats in a day times 365 days in a year (If all years had exactly 365 days but that is not true either)= 31536000 beats in a year\n\nand finally 31536000 beats in a year times 70 = 2207520000 (2.2 billion).\n\nSO your teacher is right if we take all these considerations but in life sciences the rule is that nothing is kept always constant
768641
around 40 to  50....i am very sure of that!
737839
NO. its 105\n35*3=105\n15*7=105\n\nNOT 70\n35*2=70\n15*4.666666666666666666666666666=70\n\n5 is the GCF
468158
Assuming that counting starts a 5 years of age (which is not realistic) and continues for 70 years (75 is life expectancy for a male in the USA) and that each number takes one second to count (the average would be closer to 6 seconds) and 8 hour per 24 was spent sleeping, etc., then\n\n70 * 365 = 25550 days.\n25550 * 16 hours / day = 408,800 hours.\n408,800 * 60 minutes / hour = 24,528,000 seconds.\n\n24,528,000 at 1 second or 4,080,000 at 6 seconds per number.\n\nIn actual counting trials, it has been estimated that the typical person, loosing places, getting bored and having to eat and wash occasionally would be lucky to be able to count to one million during their lifetime.
747753
if its not proven accurate, maybe that makes it proven innacurate
941865
It is quite reliable when properly applied.  It can't be trusted when:\n\n(1) it is applied so far in the past that it is extreme extrapolation of limited data.\n\n(2) the sample and its food source were radiation-protected.\n\n(3) the sample came from a situation or time where the C14/C12 ratio was different from what it is today, or is unknown.\n\nFor all these reasons, the farther back in time you try to read, the less reliable the dating.
1127748
I believe it is between 80-120 for normal with 80 being slightly retarded. most people come in betweer 90-120. At least this is what I was taught in my psychology class.