Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    5
    ReputationRep:
    Can someone explain why the probability of rolling 2 fair dice and getting a Probability of getting total 10 and getting for on green is 3/36?
    Online

    14
    ReputationRep:
    (Original post by TheAdviser101)
    Can someone explain why the probability of rolling 2 fair dice and getting a Probability of getting total 10 and getting for on green is 3/36?
    Where does the green come in to all of this? But imagine it like this. There are trivially two ways of making 10 and they are  6+4=10 \enspace \text{and} \enspace 5+5=10 .

    Now on a fair dice the probability of getting any one number is \frac{1}{6}.
    10 can be made in the following ways:
    6+4=10
    4+6=10
    5+5=10
    Each way has probability \frac{1}{6}\times\frac{1}{6}= \frac{1}{36}
    And as there are three potential ways of doing this the total probability of getting a 10 is  \frac{3}{36}
    • Thread Starter
    Offline

    5
    ReputationRep:
    (Original post by Cryptokyo)
    Where does the green come in to all of this? But imagine it like this. There are trivially two ways of making 10 and they are  6+4=10 \enspace \text{and} \enspace 5+5=10 .

    Now on a fair dice the probability of getting any one number is \frac{1}{6}.
    10 can be made in the following ways:
    6+4=10
    4+6=10
    5+5=10
    Each way has probability \frac{1}{6}\times\frac{1}{6}= \frac{1}{36}
    And as there are three potetial ways of doing this the total probability of getting a 10 is  \frac{3}{36}
    There are 2 dices green and red. Sorry, its my fault I haven't worded the question out properly. I am confused about the part in the screenshot below. I don't see how the probability becomes 3/36
    Name:  Picture1.png
Views: 19
Size:  141.2 KB
    [img]file:///C:/Users/Admin/AppData/Local/Temp/msohtmlclip1/01/clip_image002.jpg[/img]
    Online

    14
    ReputationRep:
    (Original post by TheAdviser101)
    There are 2 dices green and red. Sorry, its my fault I haven't worded the question out properly. I am confused about the part in the screenshot below. I don't see how the probability becomes 3/36
    Name:  Picture1.png
Views: 19
Size:  141.2 KB
    [img]file:///C:/Users/Admin/AppData/Local/Temp/msohtmlclip1/01/clip_image002.jpg[/img]
    I believe their answer is incorrect as the condition is P(total 10 and 4 on green) would yield a probability of \frac{1}{6}\times\frac{1}{6}= \frac{1}{36} as the events are independent. And 6 is the only number that can give a total of ten. This would imply the equation should be:
    \frac{\frac{1}{6}\times\frac{1}{  6}}{\frac{1}{6}}=\frac{1}{6}

    I believe it should be \frac{1}{36} and not \frac{3}{36} in the equation.

    Could you send me a link to the document so I can double check this though.
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    Would you rather give up salt or pepper?
    Useful resources

    Make your revision easier

    Maths

    Maths Forum posting guidelines

    Not sure where to post? Read the updated guidelines here

    Equations

    How to use LaTex

    Writing equations the easy way

    Student revising

    Study habits of A* students

    Top tips from students who have already aced their exams

    Study Planner

    Create your own Study Planner

    Never miss a deadline again

    Polling station sign

    Thinking about a maths degree?

    Chat with other maths applicants

    Can you help? Study help unanswered threads

    Groups associated with this forum:

    View associated groups
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Write a reply...
    Reply
    Hide
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.