# Roll 5 standard 6-sided dice; multiply face numbers. Find probability that result is composite number.

#### grif283

##### New member
1. If I roll 5 standard 6-sided dice and multiply the number on the face of each die, what is the probability that the result is a composite number?

2. Two distinct numbers are selected simultaneously and at random from the set {1, 2, 3, 4, 5}. What is the probability that the smaller one divides the larger one? Express your answer as a common fraction.

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#### pka

##### Elite Member
1. If I roll 5 standard 6-sided dice and multiply the number on the face of each die, what is the probability that the result is a composite number?

2. Two distinct numbers are selected simultaneously and at random from the set {1, 2, 3, 4, 5}. What is the probability that the smaller one divides the larger one? Express your answer as a common fraction.
First: Did you read the posting guidelines? If you did where is the work that you have tried? If we see your work we can better help you.

Now: Do you mean that the five face numbers are multiplied together?
Like $$\displaystyle 1\cdot 1\cdot 1\cdot 1\cdot 5=5$$ or $$\displaystyle 1\cdot 6\cdot 3\cdot 1\cdot 5=90$$

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#### grif283

##### New member
First: Did you read the posting guidelines? If you did where is the work that you have tried? If we see your work we can better help you.

Now: Do you mean that the five face numbers are multiplied together?
Like $$\displaystyle 1\cdot 1\cdot 1\cdot 1\cdot 5=5$$ or $$\displaystyle 1\cdot 6\cdot 3\cdot 1\cdot 5=90$$
yup

#### pka

##### Elite Member
So, where is your own work? You must post some effort at doing these.

#### Denis

##### Senior Member
1. If I roll 5 standard 6-sided dice and multiply the number on the face of each die, what is the probability that the result is a composite number?

2. Two distinct numbers are selected simultaneously and at random from the set {1, 2, 3, 4, 5}. What is the probability that the smaller one divides the larger one? Express your answer as a common fraction.
1,2
1,3
1,4
1,5
2,3
2,4
2,5
3,4
3,5
4,5
That's a hint...

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