// Numbas version: finer_feedback_settings {"name": "Simon's copy of Coefficient in the expansion of a multinomial,", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"functions": {}, "variable_groups": [], "metadata": {"description": "", "licence": "Creative Commons Attribution 4.0 International"}, "parts": [{"marks": 0, "showCorrectAnswer": true, "customName": "", "extendBaseMarkingAlgorithm": true, "type": "gapfill", "unitTests": [], "variableReplacementStrategy": "originalfirst", "sortAnswers": false, "prompt": "
Coefficient = ?[[0]]
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\nThe coefficient is:
\n\\[\\frac{\\var{n}!}{\\var{a}!\\var{b}!\\var{c}!\\var{d}!\\var{f}!}=\\var{ans}\\]
", "ungrouped_variables": ["a", "c", "b", "d", "f", "n", "ans"], "rulesets": {}, "statement": "What is the coefficient of $x_1^{\\var{a}}x_2^{\\var{b}}x_3^{\\var{c}}x_4^{\\var{d}}x_5^{\\var{f}}$ in the expansion of $(x_1+x_2+x_3+x_4+x_5)^{\\var{n}}$?
", "tags": [], "extensions": [], "type": "question", "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}, {"name": "Simon Thomas", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/3148/"}]}]}], "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}, {"name": "Simon Thomas", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/3148/"}]}