// Numbas version: finer_feedback_settings {"name": "Calculate probabilities from normal distribution,", "extensions": ["stats"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"tags": ["ACC1012", "checked2015", "MAS1403"], "parts": [{"prompt": "
Find the probability that in a particular week the {amount} is less than {lower} {units1}:
\nProbability = ?[[0]](to 2 decimal places)
\nFind the probability that in a particular week the {amount} is greater than {upper} {units1}:
\nProbability = ?[[1]](to 2 decimal places)
", "type": "gapfill", "showCorrectAnswer": true, "scripts": {}, "marks": 0, "gaps": [{"scripts": {}, "showPrecisionHint": false, "type": "numberentry", "showCorrectAnswer": true, "marks": 1, "minValue": "prob1-tol", "maxValue": "prob1+tol", "allowFractions": false, "correctAnswerFraction": false}, {"scripts": {}, "showPrecisionHint": false, "type": "numberentry", "showCorrectAnswer": true, "marks": 1, "minValue": "prob2-tol", "maxValue": "prob2+tol", "allowFractions": false, "correctAnswerFraction": false}]}], "preamble": {"js": "", "css": ""}, "functions": {}, "advice": "1. Converting to $\\operatorname{N}(0,1)$
\n$\\simplify[all,!collectNumbers]{P(X < {lower}) = P(Z < ({lower} -{m}) / {s}) =1 -P(Z < {m-lower}/{s})} = 1-P(z<\\var{zlower})=1 -\\var{p} = \\var{prob1}$ to 2 decimal places.
\n2. Converting to $\\operatorname{N}(0,1)$
\n$\\simplify[all,!collectNumbers]{P(X > {upper}) = P(Z > ({upper} -{m}) / {s}) = 1 -P(Z < {upper-m}/{s})} = 1-P(z<\\var{zupper})=1-\\var{p1} = \\var{prob2}$ to 2 decimal places.
", "metadata": {"description": "Given a random variable $X$ normally distributed as $\\operatorname{N}(m,\\sigma^2)$ find probabilities $P(X \\gt a),\\; a \\gt m;\\;\\;P(X \\lt b),\\;b \\lt m$.
", "notes": "\n \t\t1/1/2012:
\n \t\tCan be configured to other applications using the string variables suppplied. Included tag sc.
\n \t\t", "licence": "Creative Commons Attribution 4.0 International"}, "variablesTest": {"maxRuns": 100, "condition": ""}, "statement": "\nThe {amount}, $X$, of {stuff} is normally distributed with mean {m}k and standard deviation {s}{units1}.
\ni.e. \\[X \\sim \\operatorname{N}(\\var{m},\\var{s}^2)\\]
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