Question -Sample space in probability

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    Probability Space
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Discussion Overview

The discussion revolves around determining the sample space for an experiment involving rolling a six-sided die until a 6 is obtained. Participants explore the concept of sample space, the nature of possible outcomes, and the specifics of events defined by the number of rolls.

Discussion Character

  • Exploratory
  • Technical explanation
  • Homework-related

Main Points Raised

  • Some participants inquire about the sample space of rolling a die until a 6 appears, seeking clarification on what constitutes valid outcomes.
  • One participant suggests that the sample space includes all sequences of numbers ending with a 6, where no other 6 appears in the sequence.
  • Examples are provided to illustrate the sample space for different values of n, with specific sequences listed for n=1, n=2, and n=3.
  • There is a challenge regarding how to calculate the number of valid sequences for a given n, particularly for n=3.

Areas of Agreement / Disagreement

Participants generally agree on the definition of the sample space but differ in their understanding of how to enumerate the sequences for specific events. The discussion remains unresolved regarding the exact number of sequences for larger n values.

Contextual Notes

Some assumptions about the nature of the sequences and the counting methods for combinations are not fully explored, leaving open questions about the mathematical approach to solving for n greater than 3.

lola19991
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I would like to know how to solve the following question:
Throw a cube until you get the number 6, then stop throwing.
a) What is the sample space of the experiment?
b) Let's call the event to throw the cube n times En. How much elements from the sample space are within En?
**The cube is a standard six-sided die, with the numbers "1" thru "6" printed on the sides**
 
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lola19991 said:
I would like to know how to solve the following question:
Throw a cube until you get the number 6, then stop throwing.
a) What is the sample space of the experiment?
b) Let's call the event to throw the cube n times En. How much elements from the sample space are within En?
**The cube is a standard six-sided die, with the numbers "1" thru "6" printed on the sides**

Hi! What have you tried so far?

I'm sure you're capable of solving part a)! Remember, the sample space is the set of all possible outcomes for a random experiment. Can you list all the possible outcomes of throwing a die (exclude any exceptional cases)?
 
Joppy said:
Hi! What have you tried so far?

I'm sure you're capable of solving part a)! Remember, the sample space is the set of all possible outcomes for a random experiment. Can you list all the possible outcomes of throwing a die (exclude any exceptional cases)?

I know that the possible outcomes of throwing a die is: {1, 2, 3, 4, 5, 6}. I don't know how to start solving this problem because I've just started studying, so
I don't know how to begin...
 
The "sample space" is the set of all things that can happen. Here, where you are throwing a six sided die until you get a 6, the sample space is the set of all sequence of numbers 1, 2, 3, 4, 5, 6 which have 6 as the last number but no where else. "2, 3, 1, 5, 1, 3, 4, 6" is in the sample space. "1, 3, 2, 1, 4, 5" is not because it does not end in "6". "3, 5, 3, 4, 6, 2, 1, 3, 6" is not because there is a "6" that is not the last number in the sequence.

In event "En", throwing the dice n times, there must be the numbers "1, 2, 3, 4, 5" n-1 times followed by a 6. In how many ways can you have n-1 different combinations of those 5 numbers?

Here are some easy examples: if n= 1, n- 1= 0 and the only possible sequence is "6", 1 sequence.

If n= 2, n- 1= 1 and we can have only "16", "26", "36", "46" and "56", 5 sequences.

If n= 3, n- 1= 2 and we can have only "116", "126", "136", "146", "156", "216", "226", "236", "246", "256", "316", "326", "336", "346", "356", "416", "426" "436", "446", "456", "516", "526", "536", "546" and "556". How many are there? Do you get the idea?
 

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