An electric component for a medical xray unit is produced in lotsof size n=30. A
ID: 3051168 • Letter: A
Question
An electric component for a medical xray unit is produced in lotsof size n=30. An acceptance testing procedure is used by thepurchaser to protect against lots that contain too manynonconforming components. The procedure consists of selecting 6 components at random from the lot (without replacement) and testing them. If none of the components is nonconforming, the lot is accepted. If the lot contains two non-conforming units what is the probabilit of the lot acceptance?
a) ID the distribution. (I think it's binomial)
b) calculate the probability to 4 decimal places.
Explanation / Answer
a)
Yes this is binomial distribution.
b)
If the lot contains two non-conforming units and if we want lot to be accepted, the 6 componenets selected should not include those any of 2 non-conforming components.
selecting 6 components from 28 good components can be done in 28C6 ways
Hence required probability = 28C6/30C6 = 0.6345
We can also use the binomial distribution formula with p = 2/30 and n=6
P(X = 0) = 6C0*(2/30)^0 * (28/30)^6 = 0.6610
We see the difference in two values because binomial distribution considers with replacement. Hence we get highter probability.
Probability calculated first i.e. 0.6345 is more accurate.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.