- CFA Exams
- CFA Level I Exam
- Study Session 2. Quantitative Methods (1)
- Reading 8. Probability Concepts
- Subject 4. Multiplication Rule for Independent Events

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**CFA Practice Question**

If two six-sided dice are rolled once, what is the probability of rolling doubles (same number on each die) and a sum of six?

B. 0.250

C. 0.028

A. 0.278

B. 0.250

C. 0.028

Correct Answer: C

That is, to get 3 and 3! (1/6) x (1/6) = 0.0277

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**User Contributed Comments**
9

User |
Comment |
---|---|

vincenthuang |
should be .0277*2=.0556, coz there are two 3x3 |

cfaman |
No vincent. The probability of getting 3 in the first dice is 1/6, so is the second one. Therefore the joint probability is 1/6 x 1/6. |

katybo |
6*1/6*1/6 (11 22 33 44 55 66) |

noonah |
Vincent reasoning would be correct if the dice were rolled twice. |

Yooo |
Vincent, I own a casino. Stop by any time. |

jwebbs |
all i know is there's 36 different combinations, and only 1 rolls a double and equals 6. 1/36=.027777 |

soarer1 |
Common sense would indicate 0.028 too. |

alyl21 |
This is more common sense than anything. 1) to get sum of 6, here are the combis 5,1| 2,4| 3,3| 4,2| 1,5 Here are 5 pairs, of these 5 pairs, only one pair are doubles, that is 3,3 this is one possibility of out 36 different results from 2 throws of a 6 faced die. 1/36 is the answer |

daxian610 |
alyl21- Nice ! |