Question

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Answer 1

@kropot72

Answer 2

Just wanted to know if I'll be needing the combination rule in this question.

Answer 3

Well, 40 of them will have 15 or more.

Answer 4

You only draw 5 times.

Answer 5

First time you draw, you have a 40/50, there will be 39 good ones and 49 remaining.

Answer 6

So it will be 39/49 on the next turn, and it will be 38/48

Answer 7

from where did you get 40?

Answer 8

50-10=40

Answer 9

@kropot72

Answer 10

750

Answer 11

I want to understand this question

Answer 12

The probability of a cookie in the bag of 50 being 'defective' is 10/50 = 0.2.
The probability of a cookie being 'good' is therefore 1 - 0.2 = 0.8.
The probability of finding that all cookies in a sample of 5 are 'good' is given by:
\[\large (0.8)^{5}=you\ can\ calculate\]

Answer 13

@kropot72

Answer 14

How will I be able to find the probability that 10 cookies had less than 15 chips.

Answer 15

The number of chips in the cookie is just a criterion for determining whether a cookie is acceptable (good, 15 or more chips) or unacceptable (defective, fewer than 15 chips). The number of defective cookies in the bag of 50 is given as 10 cookies in the question. The number of chips plays no part in the calculation.

Answer 16

"How will I be able to find the probability that 10 cookies had less than 15 chips."
The question tells you that 10 out of the 50 cookies have fewer than 15 chips.

Answer 17

The question is asking for the probability of finding none of the 10 'defective' cookies in a random sample of 5 cookies. The probability of a cookie having 15 or more chips is 0.8. Therefore the probability of finding that all five cookies in a sample of 5 have 15 or more chips is (0.8)^5.