![](\"resources/question-resources/halogen_LED_900.png\")
Used for LANTITE preparation (Australia). NA = Number & Algebra strand. Students calculate the cost of the halogen globes given electricity cost, number of globes, number of years, replacement cost and lifespan of globes. Some of these variables are randomly selected. There are more than 10 different versions of this question.
", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "The government encourages people to switch to energy efficient devices. One way to save is to replace halogen light globes with LED light globes.
\nThe infographic below shows the electricity cost of using a halogen light globe and an equivalent LED light globe for 1 year. It also gives the average lifespan for each type of globe.
\n
https://accreditedpower.com.au/led-upgrades/nsw-home-led-upgrade-program/
", "advice": "Halogen globe costs
The school currently has {globes} new halogen globes, and each halogen globe will need to be replaced every 2 years.
\nOver the next {years} years, the globes will each need to be replaced {trunc(years/2)} times once .
\nThe cost of replacing {globes} halogen globes twice is given by {trunc(years/2)} x {globes} x \\${split(dpformat(halogencost,2,\"si-en\"),\".00\")[0]} = \\${split(dpformat(trunc(years/2)*globes*halogencost,2,\"si-en\"),\".00\")[0]}
\nEach halogen globe costs \\$35.13 per year in electricity, and there are {globes} globes which will be used for {years} years.
\nThe electricity cost for the halogen globes over the {years} years is {globes} x {years} x \\$35.13 = \\${haleleccost}
\nTo obtain the total cost for the halogen lighting, add the globe cost and the electricity cost.
\n\\${split(dpformat(trunc(years/2)*globes*halogencost,2,\"si-en\"),\".00\")[0]} + \\${haleleccost} = \\${totalhalogencost}
\nRounded to the nearest dollar, the cost of the halogen lighting over the next {years} years is \\${formatnumber(precround(parsenumber(totalhalogencost,\"si-en\"),0),\"si-en\")}
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", "templateType": "randrange", "can_override": false}, "halogencost": {"name": "halogencost", "group": "Ungrouped variables", "definition": "random(4.5 .. 6.5#0.25)", "description": "The cost of one halogen globe.
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", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["years", "halogencost", "globes", "haleleccost", "totalhalogencost", "finalanswer"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "A school chooses NOT to replace the {globes} halogen globes in their main learning space.
\nHow much will this school pay for this halogen lighting during the next {years} years?
\nAssume that the existing halogen globes would first need replacement in 2 years time, and that replacement halogen globes cost {currency(halogencost,\"\\$\",\"\")} each.
\nIn your calculations, include the cost of buying replacement halogen globes every 2 years, and the cost of the electricity.
\nDo not include the money they lose by not converting to LED globes.
\nRound your answer to the nearest dollar, but do not enter the $ sign.
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