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## #1 2023-11-19 11:29:20

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Probability of Red Section

A map has 5 color sections. One of the sections is red. What is the probability of selecting the red section blindfolded?

P(red section) = one red/(5 colors)

P(red section) = 1/5

You say?

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## #2 2023-11-20 00:08:01

Bob
Registered: 2010-06-20
Posts: 9,903

### Re: Probability of Red Section

Correct if we assume the sections are equal in area. If this is not the case then it is not possible to determine the probability.

B

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #3 2023-11-20 15:26:49

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Re: Probability of Red Section

Bob wrote:

Correct if we assume the sections are equal in area. If this is not the case then it is not possible to determine the probability.

B

Can you explain what you mean?

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## #4 2023-11-20 15:52:15

amnkb
Member
Registered: 2023-09-19
Posts: 194

### Re: Probability of Red Section

Bob wrote:

Correct if we assume the sections are equal in area. If this is not the case then it is not possible to determine the probability.

sologuitar wrote:

Can you explain what you mean?

what would happen if one of the sections is, say, half of the wheel

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## #5 2023-11-20 18:16:46

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Re: Probability of Red Section

amnkb wrote:
Bob wrote:

Correct if we assume the sections are equal in area. If this is not the case then it is not possible to determine the probability.

sologuitar wrote:

Can you explain what you mean?

what would happen if one of the sections is, say, half of the wheel

In that case, the probability is 1/2.

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## #6 2023-11-20 20:49:50

Bob
Registered: 2010-06-20
Posts: 9,903

### Re: Probability of Red Section

That's right and demonstrates why I say solving depends on whether the regions are equal.  Maybe the questioner intended you would assume that. But it is also possible that the intended point of the question is for you to realise that insufficient information has been given.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #7 2023-11-21 05:08:42

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Re: Probability of Red Section

Bob wrote:

That's right and demonstrates why I say solving depends on whether the regions are equal.  Maybe the questioner intended you would assume that. But it is also possible that the intended point of the question is for you to realise that insufficient information has been given.

Bob

Insufficient data has been given. How do you know this?

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