How Do You Calculate Samples Containing Defective Widgets?

  • Thread starter Thread starter liahow
  • Start date Start date
  • Tags Tags
    Counting Formulas
liahow
Messages
6
Reaction score
0
I am working on a problem in which there are 100 widgets. I need to find how many samples of size 5 there are, which I found to be 75,287,520. No problem there. I am not sure how to go about the next part, however. In the original set of 100 widgets, 3 are broken. How many of the samples of 5 contain at least one of these broken widgets? No idea how to do that. Can someone please help? Thanks!
 
Physics news on Phys.org
The probability that a given set of 5 widgets has no broken ones is
(97*96*95*94*93)/(100*99*98*97*96). Multiply that by the total number of combinations to get the number without any broken.
 
If you want to use the basic counting formula, remove the 3 bad widgets from the set and you have 97. Calculate the number of samples of size 5 for the 97 and subtract from the number of samples of 5 for 100.
 

Thread 'Here's a Statistics problem for game of Polo (or Hockey if you like)'

Namaste & G'day Postulate: A strongly-knit team wins on average over a less knit one Fundamentals: - Two teams face off with 4 players each - A polo team consists of players that each have assigned to them a measure of their ability (called a "Handicap" - 10 is highest, -2 lowest) I attempted to measure close-knitness of a team in terms of standard deviation (SD) of handicaps of the players. Failure: It turns out that, more often than, a team with a higher SD wins. In my language, that...
View full post »

Thread 'Roulette wheel physics and probability'

Hi all, I've been a roulette player for more than 10 years (although I took time off here and there) and it's only now that I'm trying to understand the physics of the game. Basically my strategy in roulette is to divide the wheel roughly into two halves (let's call them A and B). My theory is that in roulette there will invariably be variance. In other words, if A comes up 5 times in a row, B will be due to come up soon. However I have been proven wrong many times, and I have seen some...
View full post »

Similar threads

Non-Parametric Testing for Widget Defectivity: Sample Size Considerations
Replies
5
Views
2K
I Is Unbiasedness in Estimation Truly Reflective of Population Parameters?
Replies
9
Views
2K
I How far and how close to p=0.05 for statistical significance?
Replies
24
Views
5K
I Correct understanding of confidence intervals....
Replies
22
Views
3K
I Optimizing Defective Rates with Bayes' Formula
Replies
17
Views
2K
I How to implement proper error estimation using MC
Replies
3
Views
2K
How Do You Calculate the Probability of Bus Frame Cracks?
Replies
1
Views
3K
How to calculate Standard Error for unequal sample sizes
Replies
25
Views
12K
A Confused about magnitude of error
Replies
18
Views
3K
I How to compare two data sets with multiple samples
Replies
8
Views
2K

Hot Threads

Recent Insights

Back
Top