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(a) P({thing[0]})xP({thing[1]})={x}x{y}={a1}

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Next round to 2 decimal places to get {a1d}

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(b) P(not - {thing[0]})xP(not - {thing[1]})$=(1-\\var{x})\\times (1-\\var{y})=\\var{a2}$

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Next round to 2 decimal places to get {a2d}

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(c) 1- (answer to part (b))=1-{a2d}={a3d}

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(d) ( (1-{x})x {y})+( (1-{y})x {x})={a4}

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Next round to 2 decimal places to get {a4d}

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", "rulesets": {}, "parts": [{"precisionType": "dp", "prompt": "

What is the probabilty that both of these events occur?

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What is the probabilty that neither of these events occur?

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What is the probabilty that at least one of these two events will occur?

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What is the probabilty that only one of the two events occur?

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The probability that {thing[0]} is {x}, while the probability that {thing[1]} is {y}. Assume that these two events are independent. Give all answers correct to two decimal places.

", "variable_groups": [], "variablesTest": {"maxRuns": 100, "condition": ""}, "variables": {"a4d": {"definition": "precround((1-x)*y+(1-y)*x,2)", "templateType": "anything", "group": "Ungrouped variables", "name": "a4d", "description": ""}, "a1d": {"definition": "precround(x*y,2)", "templateType": "anything", "group": "Ungrouped variables", "name": "a1d", "description": ""}, "a1": {"definition": "x*y", "templateType": "anything", "group": "Ungrouped variables", "name": "a1", "description": ""}, "thing": {"definition": "random(['there will be a change in government in Ireland next year ', 'Ireland will win the rugby world cup next year'],['it will rain in Qumar on any given day','it will rain in Timbucktoo on any given day'],['shares in the Bank of Lapland will rise on any given day','shares in the Bank of Never Never Land will rise on any given day'])", "templateType": "anything", "group": "Ungrouped variables", "name": "thing", "description": ""}, "a3": {"definition": "1-a2", "templateType": "anything", "group": "Ungrouped variables", "name": "a3", "description": ""}, "a2": {"definition": "(1-x)*(1-y)", "templateType": "anything", "group": "Ungrouped variables", "name": "a2", "description": ""}, "a2d": {"definition": "precround((1-x)*(1-y),2)", "templateType": "anything", "group": "Ungrouped variables", "name": "a2d", "description": ""}, "a4": {"definition": "(1-x)*y+(1-y)*x", "templateType": "anything", "group": "Ungrouped variables", "name": "a4", "description": ""}, "a3d": {"definition": "precround(1-a2,2)", "templateType": "anything", "group": "Ungrouped variables", "name": "a3d", "description": ""}, "y": {"definition": "random(0.01..0.99#0.01)", "templateType": "randrange", "group": "Ungrouped variables", "name": "y", "description": ""}, "x": {"definition": "random(0.01..0.9#0.01)", "templateType": "randrange", "group": "Ungrouped variables", "name": "x", "description": ""}}, "metadata": {"description": "

rebelmaths

", "licence": "Creative Commons Attribution 4.0 International"}, "type": "question", "showQuestionGroupNames": false, "question_groups": [{"name": "", "pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": []}], "contributors": [{"name": "Julie Crowley", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/113/"}]}]}], "contributors": [{"name": "Julie Crowley", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/113/"}]}