// Numbas version: exam_results_page_options
{"name": "Compare prices and values using the unit cost method", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"metadata": {"description": "", "licence": "All rights reserved"}, "preamble": {"css": "", "js": ""}, "advice": "<p>We have two different prices: the pre-packaged price is given for a decimal quantity of kg, while the loose price is in kg. If we are to compare prices using prices per kg, the loose price is already in the correct form, but we need to convert the pre-packaged price to a price for 1kg. So&nbsp;we need to divide the pre-packaged price by that decimal quantity to give the unit price in \\$/kg. Once that value is known, we compare it directly with the price per kilogram to buy at the loose produce price.</p>", "tags": [], "functions": {}, "parts": [{"stepsPenalty": 0, "marks": 0, "variableReplacements": [], "unitTests": [], "extendBaseMarkingAlgorithm": true, "showCorrectAnswer": true, "type": "information", "prompt": "<p>At a local produce market, {fruit} are sold pre-packaged or loosely. You can buy {fruit} in {packsize}kg pre-packaged bags for \\${packprice} or loosely for \\${looseprice} per kg. Use the unit cost method to decide which is the best value for money.</p>", "showFeedbackIcon": true, "customMarkingAlgorithm": "", "scripts": {}, "steps": [{"notationStyles": ["plain", "en", "si-en"], "marks": 1, "correctAnswerStyle": "plain", "mustBeReduced": false, "variableReplacements": [], "unitTests": [], "extendBaseMarkingAlgorithm": true, "showCorrectAnswer": true, "correctAnswerFraction": false, "allowFractions": false, "type": "numberentry", "prompt": "<p>If the unit to compare is kilograms, then the unit cost for the pre-packaged {fruit} in \\$/kg is</p>", "showFeedbackIcon": true, "customMarkingAlgorithm": "", "scripts": {}, "minValue": "{packprice}/{packsize}-0.005", "maxValue": "{packprice}/{packsize}+0.005", "mustBeReducedPC": 0, "variableReplacementStrategy": "originalfirst"}, {"choices": ["Loose purchase of {fruit}", "Pre-package purchase of {fruit}"], "displayColumns": 0, "maxMarks": 0, "displayType": "radiogroup", "marks": 0, "shuffleChoices": false, "variableReplacements": [], "unitTests": [], "extendBaseMarkingAlgorithm": true, "showCorrectAnswer": true, "matrix": "[if({looseprice}<{packprice}/{packsize},1,0),if({packprice}/{packsize}<{looseprice},1,0)]", "type": "1_n_2", "prompt": "<p>The price for purchasing {fruit} loosely is already given in terms of a price per kg. Comparing your two unit prices, select the option which provides the best value for money.</p>", "showFeedbackIcon": true, "customMarkingAlgorithm": "", "scripts": {}, "minMarks": 0, "showCellAnswerState": true, "variableReplacementStrategy": "originalfirst"}], "variableReplacementStrategy": "originalfirst"}], "rulesets": {}, "ungrouped_variables": ["fruit", "packsize", "packprice", "looseprice"], "extensions": [], "variablesTest": {"maxRuns": 100, "condition": ""}, "variables": {"packprice": {"templateType": "randrange", "description": "", "group": "Ungrouped variables", "definition": "random(2..8#0.34)", "name": "packprice"}, "fruit": {"templateType": "anything", "description": "", "group": "Ungrouped variables", "definition": "random('apples','bananas','oranges','potatoes','tomatoes')", "name": "fruit"}, "packsize": {"templateType": "randrange", "description": "", "group": "Ungrouped variables", "definition": "random(0.25..0.8#0.05)", "name": "packsize"}, "looseprice": {"templateType": "randrange", "description": "", "group": "Ungrouped variables", "definition": "random(5..18#0.37)", "name": "looseprice"}}, "name": "Compare prices and values using the unit cost method", "variable_groups": [], "statement": "<p>The unit cost method is a way of comparing the price or value of two or more things when those prices or values do NOT refer to the same quantity. For example, we might want to know whether it's better to buy a 750g bag of apples priced at \\$5, or to buy loose apples at \\$5.50 per kg.</p>\n<p>The method involves</p>\n<ol>\n<li>Decide on your \"unit\" of comparison</li>\n<li>Converting the prices or values to equivalents for that unit</li>\n</ol>", "type": "question", "contributors": [{"name": "Dann Mallet", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/800/"}]}]}], "contributors": [{"name": "Dann Mallet", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/800/"}]}