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On a penalty kick, Bob scores a goal 75% of the time. Over the course of a game, Bob kicks 8 penalty kicks.
Find the expected number of goals Bob scores during the game from penalty kicks.
Find the probability that Bob scores 8 goals.
Find the probability that Bob scores more than 5 goals.
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James is sitting a multiple choice exam with 15 questions. Each question has 3 answer choices, of which only one is correct.
James randomly picks an answer on each question. Let X represent the number of questions James answers correctly.
State whether X is discrete or continuous.
Write down the value of E(X).
Find the probability that
X=7,
3<X<10.
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The masses, in grams, of chocolate bars produced by a factory can be modelled by a normal distribution with mean 100g and standard deviation 0.6g. A chocolate bar can only be packaged if its mass is greater than 99g, otherwise is it melted back into the production line.
Find the probability that a randomly selected chocolate bar is packaged.
On a given day, the number of chocolate bars packaged is 5000.
Estimate, to the nearest 10, the number of chocolate bars that are melted back that day.
Given that a bar has a mass of less than 101g, find the probability it will be melted down.
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Let R be the value of a roll on 6-sided die. The probability distribution for R is shown in the following table.
Sally rolls the dice 100 times, and records 25 rolls of 6.
Explain why this is not inconsistent with the table.
Josh plays a game using this dice. He pays $4 to roll the dice, and earns back the value of his roll in dollars.
Determine the value of p and the value of q such that the game is fair.
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