Probability

[Sirji]

80 % people in a city wear masks while going outside their home. If a sample of 10 people will be surveyed what is the probability that

(a) none will be found without mask,

(b) one will be found without mask,

(c) all will be found without mask,

 

[Deleted member 4993]

80 % people in a city wear masks while going outside their home. If a sample of 10 people will be surveyed what is the probability that

(a) none will be found without mask,

(b) one will be found without mask,

(c) all will be found without mask,

Please show us what you have tried and exactly where you are stuck.

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Please share your work/thoughts about this problem.

 

[Dr.Peterson]

80 % people in a city wear masks while going outside their home. If a sample of 10 people will be surveyed what is the probability that

(a) none will be found without mask,

(b) one will be found without mask,

(c) all will be found without mask,

In no particular order ...

What is the probability that a given individual will be wearing a mask?

What is the probability that this will be true of all 10 people?

What is the probability that a given individual will not be wearing a mask?

What is the probability that this will be true of all 10 people?

For (b), you'll have to decide whether it means "exactly one" or "at least one".

 

[Sirji]

In no particular order ...

What is the probability that a given individual will be wearing a mask?

What is the probability that this will be true of all 10 people?

What is the probability that a given individual will not be wearing a mask?

What is the probability that this will be true of all 10 people?

For (b), you'll have to decide whether it means "exactly one" or "at least one".

What is the probability that this will be true for all 10 people

 

[Dr.Peterson]

What is the probability that this will be true for all 10 people

Have you learned about finding the probability of A and B, when the events are independent? Please show us whatever you know, because we want to help you use that to solve the problem.

 

[Sirji]

Have you learned about finding the probability of A and B, when the events are independent? Please show us whatever you know, because we want to help you use that to solve the problem.

if the probability of event A is p(A) and the probability of event B is P(B) then the probability of both events happening at the same time. P(A)*P(B)