// Numbas version: exam_results_page_options
{"name": "Mean and standard deviation from a frequency table with classes 1c", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"metadata": {"licence": "Creative Commons Attribution 4.0 International", "description": "<p>Scores&nbsp; in 20 games and frequency given -- calculate mean.</p>\n<p>rebelmaths</p>"}, "rulesets": {}, "tags": [], "advice": "<p></p>\n<p></p>", "statement": "<p>The following gives the age distribution of the 160 members of a local athletics&nbsp;club</p>\n<table border=\"1\" height=\"91\" width=\"573\">\n<tbody>\n<tr>\n<th align=\"left\">Class (Age in years)</th>\n<th>frequency (No of members)</th>\n</tr>\n<tr>\n<th align=\"left\">{q-5} but less than {q+5}</th>\n<th>{a}</th>\n</tr>\n<tr>\n<th align=\"left\">{p-5} but less than {p+5}</th>\n<th>{b}</th>\n</tr>\n<tr>\n<th align=\"left\">{s-5} but less than {s+5}</th>\n<th>{c}</th>\n</tr>\n<tr>\n<th align=\"left\">{r-5} but less than {r+5}</th>\n<th>{d}</th>\n</tr>\n<tr>\n<th align=\"left\"></th>\n<th></th>\n</tr>\n</tbody>\n</table>", "extensions": [], "functions": {}, "ungrouped_variables": ["a", "c", "b", "d", "q", "p", "s", "r", "t", "stdev", "mean", "x", "Total", "data", "mode", "Median"], "variablesTest": {"maxRuns": 100, "condition": ""}, "preamble": {"js": "", "css": ""}, "variable_groups": [], "name": "Mean and standard deviation from a frequency table with classes 1c", "parts": [{"showPrecisionHint": true, "correctAnswerFraction": false, "notationStyles": ["plain", "en", "si-en"], "mustBeReducedPC": 0, "scripts": {}, "type": "numberentry", "precisionPartialCredit": 0, "mustBeReduced": false, "minValue": "mean", "prompt": "<p></p>\n<p>Calculate the mean of the data to the nearest whole number.</p>", "showCorrectAnswer": true, "marks": "2", "maxValue": "mean", "showFeedbackIcon": true, "precision": 0, "precisionMessage": "You have not given your answer to the correct precision.", "variableReplacementStrategy": "originalfirst", "strictPrecision": false, "allowFractions": false, "correctAnswerStyle": "plain", "precisionType": "dp", "variableReplacements": []}, {"showPrecisionHint": true, "correctAnswerFraction": false, "notationStyles": ["plain", "en", "si-en"], "mustBeReducedPC": 0, "scripts": {}, "type": "numberentry", "precisionPartialCredit": 0, "mustBeReduced": false, "minValue": "stdev", "prompt": "<p>Calculate the standard deviation&nbsp;of the data to the nearest whole number.</p>", "showCorrectAnswer": true, "marks": "4", "maxValue": "stdev", "showFeedbackIcon": true, "precision": 0, "precisionMessage": "You have not given your answer to the correct precision.", "variableReplacementStrategy": "originalfirst", "strictPrecision": false, "allowFractions": false, "correctAnswerStyle": "plain", "precisionType": "dp", "variableReplacements": []}], "variables": {"d": 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