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Subject: "Estimation of tanks"     Previous Topic | Next Topic
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Conferences The CTK Exchange College math Topic #48
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DannyJ111 (Guest)
Jan-17-01, 02:12 AM (EST)
"Estimation of tanks"

During WWII the united states neaded to estimate the number of tanks that the Nazis had. The US captured 4 German tanks. Each tank was numbered. The number coincides with that of which was being produced. if the number was 42 than that tank would be the fortysencond tank built. If the numbers on the 4 tanks were 13 47 39 61, how, if you do not know the total number of tanks, estimate how many tanks the nazis had produced? Is ther a formula I am missing here that could help me?!! Help!

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Charter Member
672 posts
Jan-17-01, 02:46 AM (EST)
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1. "RE: Estimation of tanks"
In response to message #0
   This probably has to do with the Bayesian approach. You may assume that if the total number was N, then there's a probability of 1/2 to capture a tank with the number above N/2, or below N/2 for that matter. Similarly the probabilities to capture a tank with the number below N/3, above 2N/3, and in between are all 1/3.

Thus, e.g. P(13,47,39,61|N=200) - probability to capture ##13, 47, 39, 61 provided the total was 200 - is, roughly speaking (1/3)4. You are interested in the another conditional probablity, viz. P(N=200|13,47,39,61) - probability that the total number was 200 provided ##13, 47, 39, 61 have been captured.

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