// Numbas version: exam_results_page_options {"name": "Blathnaid's copy of Probability independent 2 events", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"tags": ["rebelmaths"], "extensions": [], "parts": [{"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.

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rebelmaths

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

\n

Next round to 2 decimal places to get {a1d}

\n

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

\n

Next round to 2 decimal places to get {a2d}

\n

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

\n

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

\n

Next round to 2 decimal places to get {a4d}

\n

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