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A six-sided fair die is rolled 4 times in a row. The probability of getting a 4 only on the last trial is

User Josh Pittman
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2 Answers

19 votes
19 votes

Answer: 125/1296

Step-by-step explanation:

User Lory Huz
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28 votes
28 votes

Answer:

Explanation:

P(4 only on the last roll) = P(not 4 on first roll) and P(not 4 on the second roll) and P(not 4 on the third roll) and P(4 on the last roll)

in probability and = multiplication

P( not roll a 4) = 1 - P(roll a 4)

P(4 only on the last roll) = 1-P(4) * 1-P(4) *1-P(4) * P(4)

P(4) = 1 (1 time# 4 appears on the die)/6 (#of possible outcomes 1,2,3,4,5,6)

P(4 only on the last roll) = 1-(1/6) * 1-(1/6) *1-(1/6) * (1/6)

P(4 only on the last roll) =(5*5*5*1)/(6*6*6*6) = 125/1296

User Niniki
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