Question

These are the sides of a octahedron used to play a game. What is the probability for Jack to roll a 3 and then an even number.

Answer 1

Answer:

1/16

Explanation:

The number of sides in the octahedron = 8

$\text{The probability for Jack to roll a 3}=\frac{1}{8}$

The number of even numbers in the octahedron is 4. i.e. {2,3,4,8}

$\begin{gathered} \text{The probability for Jack to roll an even number}=\frac{4}{8} \\ =\frac{1}{2} \end{gathered}$

Therefore, the probability for Jack to roll a 3 AND then an even number:

$\begin{gathered} =\frac{1}{8}\times\frac{1}{2} \\ =\frac{1}{16} \end{gathered}$

Note: Whenever the word AND is used, we multiply the individual probabilities.

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