I got this question from my professor for homework and I want to see what some /sci/tards get. Explain your reasoning. I got 5000 +/-500
>The following type of question is called a Fermi question, and you are to do it without using anything except your pencil and paper: How many average-sized sewing needles will fit into an average-sized coffee mug?
no takers?
>>8181992
No this Fermi problem is boring.
>>8181994
pussy
>>8181977
randomly packed, or orderly, one next to the other?
(pi(r^2)h)subscrpt1/(pi(r^2)h)subscrpt2 - some trigonometric function.
Assuming that the answer doesn't have be given as an absolute value.
>>8181977
Okay, so the average coffee mug is about 5 inches in diameter and 5 inches in height. Volume=h*r^2*pi. 5*2.5*2.5*3.14149. But we just care about the estimate, so we'll round that to 5*4*3. 60 cubic inches. The average pin is about 2 inches long and pretty thin. Let's say they're a tenth of an inch. Volume is 2*0.1*0.1*3.14159. Let's just round that to 2*0.01*3, or 6*0.01, or 0.06. That's about 0.1.
So, 60 cubic inches of space and 0.1 cubic inches per pin. 60/0.1 is the same as multiplying by 10, so about 600. If the pins were smaller, we could probably go all the way up to 1,000, which is in the same order of magnitude as your answer.
Fermi estimates are going to change based on the assumptions you make, and are made so that you can get somewhere around the order of magnitude of the answer. As long as you can justify it and your assumptions make sense, you're probably good.
>tfw they asked me Fermi problems on my last job interview
>>8182019
what was the problem?
>>8182028
>How many cows are there in the US?
>>8182019
The point of those problems is to make sure that you're able to make logical leaps to get an estimate
But they're pretty bullshit because once you know what a fermi estimate is, you know how to solve them
>>8182030
>The point of those problems is to make sure that you're able to make logical leaps to get an estimate
well, in my poetry, they were meant to check if you can wipe your own ass for yourself, but it amounts to the same.
>>8182029
>A cow weighs 2000lbs
>about 750lbs of edible meat
>average american consumes 1 lb of cow meat a week
>1 gallon of milk a week
>1 cow can produce 20 gallons a week
>200,000,000 ppl in US eat meat
(2*10^8*50*50)/(750*20)
(5*10^11)/(1.5*10^4)
3.5*10^7
35,000,000 cows
(
>>8182029
what was the answer you came up with?
>>8182040
Wow it's 39,000,000
>>8181977
i got 17000
>>8182041
I also tried something similar with meat and milk consumption. But since the numbers came from my own consumption, I came up with something like 5.5e7. Yes, I'm fat.
