What is the probability of rolling three six-sided dice, and getting a different number on each die?

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What is the probability of rolling three six-sided dice, and getting a different number on each die?

A. 1/12
B. 1/3
C. 4/9
D. 5/9
E. 7/18



OA D

Source: Magoosh

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BTGmoderatorDC wrote:
Sun Jan 23, 2022 5:22 pm
What is the probability of rolling three six-sided dice, and getting a different number on each die?

A. 1/12
B. 1/3
C. 4/9
D. 5/9
E. 7/18



OA D

Source: Magoosh
P(getting a different number on each die) = P(1st roll is ANY number AND 2nd roll is different from 1st roll AND 3rd roll is different from 1st and 2nd rolls)
= P(1st roll is ANY number) x P(2nd roll is different from 1st roll) x P(3rd roll is different from 1st and 2nd rolls)
= 6/6 x 5/6 x 4/6
= 5/9

Answer: D
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