Probability
- Thread starter thatgirl
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Hi.
Do you know anything about this process, yet? I mean, are you able to make a start?
Please show your work, so far.
If you do not understand the question, or you're stuck on one or more concepts, then please ask a question.
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You can only use combinations like that if you know how many you're choosing from. Like, out of 10 different cards, how many ways are there to choose two of them. That's not what this problem is asking. Besides, you don't need to know how many total products the factory produces.
What you know is that EACH product has a 5 percent chance of being defective. So, when you pick the first one, there's a 5 percent chance that it's defective. Then, when you pick the second one, there's also a 5 percent chance that it's defective. Let's stop there and see what we've got.
A) Chance that two are defective, out of two that I've picked: rule of multiplication.
B) Chance that exactly one of the two I've picked is defective: also the rule of multiplication, but you have to use the probability that the first one is defective, and the second one is not defective.
Can you proceed with that hint? And then, take it up to choosing 10. You'll start to notice a pattern that will help after three or four, probably.
What you know is that EACH product has a 5 percent chance of being defective. So, when you pick the first one, there's a 5 percent chance that it's defective. Then, when you pick the second one, there's also a 5 percent chance that it's defective. Let's stop there and see what we've got.
A) Chance that two are defective, out of two that I've picked: rule of multiplication.
B) Chance that exactly one of the two I've picked is defective: also the rule of multiplication, but you have to use the probability that the first one is defective, and the second one is not defective.
Can you proceed with that hint? And then, take it up to choosing 10. You'll start to notice a pattern that will help after three or four, probably.
Binomial probability. \(\displaystyle \binom n k \cdot p^{k}\cdot (1-p)^{n-k}\)
where n=10, k=2 and p=.05
Continue?.
When you see 'at least 1', find the probability of none and subtract from 1.
Use the same method as above only with k=0, then subtract that result from 1.