Jacob, Amelie and Reuben each roll a fair six-sided dice - OCR - GCSE Maths - Question 21 - 2019 - Paper 1
Question 21
Jacob, Amelie and Reuben each roll a fair six-sided dice.
What is the probability that all three roll a number less than 3?
Give your answer as a fraction in its si... show full transcript
Worked Solution & Example Answer:Jacob, Amelie and Reuben each roll a fair six-sided dice - OCR - GCSE Maths - Question 21 - 2019 - Paper 1
Step 1
Calculate individual probabilities
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Answer
On a fair six-sided die, the numbers less than 3 are 1 and 2. Thus, there are 2 favorable outcomes out of 6 possible outcomes. The probability for one person to roll a number less than 3 is:
P(<3)=62=31
Step 2
Calculate the probability for all three
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Answer
Since Jacob, Amelie, and Reuben roll independently, we multiply their probabilities:
P(all<3)=P(Jacob<3)×P(Amelie<3)×P(Reuben<3)
Substituting the individual probabilities:
P(all<3)=(31)×(31)×(31)=271
Step 3
Final answer
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Answer
Thus, the probability that all three roll a number less than 3 is: