// Numbas version: exam_results_page_options {"name": "Q7 (Calculate the estimate, actual and from these the percentage error)", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"functions": {"tens": {"definition": "random(35..80#0.01)", "type": "number", "language": "jme", "parameters": []}, "hun": {"definition": "random(301..599)", "type": "number", "language": "jme", "parameters": []}, "sin": {"definition": "random(3..8#0.01)", "type": "number", "language": "jme", "parameters": []}, "hun1": {"definition": "random(400..600)", "type": "number", "language": "jme", "parameters": []}}, "ungrouped_variables": ["num1", "num2", "num3", "num4", "num5", "num7", "num6", "num8", "num9", "num10", "num11", "num12", "num13", "num14", "num15", "num16", "num17", "num18", "num19", "num20", "num21", "ans11", "ans21", "ans31", "ans41", "ans51", "ans61", "ans12", "ans22", "ans32", "ans42", "ans52", "ans62", "ans13", "ans23", "ans33", "ans43", "ans53", "ans63"], "name": "Q7 (Calculate the estimate, actual and from these the percentage error)", "tags": ["rebelmaths"], "preamble": {"css": "", "js": ""}, "advice": "

When rounding off a number to one significant place, round to the left most figure of the number, like below;

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$367 = 400$

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$38 = 40$

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$71 = 70$

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$3.79 = 4$

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$65.13 = 70$

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$215 = 200$

\n

\n

Part 1:

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Estimate value with each number rounded to one significant place:

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$\\frac{(\\var{num1} \\times \\var{num2})}{(\\var{num3} \\times \\var{num4})}$ 

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Round numbers to one significant number:

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$\\var{num1} = ${siground(num1,1)}

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$\\var{num2} = ${siground(num2,1)}

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$\\var{num3} = ${siground(num3,1)}

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$\\var{num4} = ${siground(num4,1)}

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Answer:

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$= \\var{ans11}$

\n

\n

Part 2:

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Actual value:

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$\\frac{(\\var{num1} \\times \\var{num2})}{(\\var{num3} \\times \\var{num4})} = \\var{ans12}$

\n

\n

Part 3:

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Percentage error:

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$abs(\\frac{\\var{ans12} - \\var{ans11}}{\\var{ans11}}) \\times 100 = \\var{ans13}$%

", "rulesets": {}, "parts": [{"prompt": "

$\\frac{\\var{num1} \\times \\var{num2}}{\\var{num3} \\times \\var{num4}}$

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Estimate:       [[0]]

\n

Actual:          [[1]]

\n

% Error:        [[2]]%

", "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "gaps": [{"allowFractions": false, "variableReplacements": [], "maxValue": "{ans11}", "minValue": "{ans11}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"allowFractions": false, "variableReplacements": [], "maxValue": "{ans12}", "minValue": "{ans12}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"precisionType": "dp", "integerPartialCredit": 0, "precisionMessage": "You have not given your answer to the correct precision.", "integerAnswer": true, "allowFractions": false, "variableReplacements": [], "maxValue": "{ans13}+1", "strictPrecision": false, "minValue": "{ans13}-1", "variableReplacementStrategy": "originalfirst", "precisionPartialCredit": 0, "correctAnswerFraction": false, "showCorrectAnswer": true, "precision": "1", "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}], "showCorrectAnswer": true, "scripts": {}, "marks": 0, "type": "gapfill"}, {"prompt": "

$\\frac{\\var{num5} + \\var{num6}}{\\var{num7}}$

\n

Estimate:       [[0]]

\n

Actual:          [[1]]

\n

% Error:        [[2]]%

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$\\frac{\\var{num8} \\times \\var{num9}}{\\var{num10}}$

\n

Estimate:      [[0]]

\n

Actual:          [[1]]

\n

% Error:        [[2]]%

", "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "gaps": [{"allowFractions": false, "variableReplacements": [], "maxValue": "{ans31}", "minValue": "{ans31}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"integerPartialCredit": 0, "integerAnswer": true, "allowFractions": false, "variableReplacements": [], "maxValue": "{ans32}", "minValue": "{ans32}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"precisionType": "dp", "precisionMessage": "You have not given your answer to the correct precision.", "allowFractions": false, "variableReplacements": [], "maxValue": "{ans33}+1", "strictPrecision": false, "minValue": "{ans33}-1", "variableReplacementStrategy": "originalfirst", "precisionPartialCredit": 0, "correctAnswerFraction": false, "showCorrectAnswer": true, "precision": "1", "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}], "showCorrectAnswer": true, "scripts": {}, "marks": 0, "type": "gapfill"}, {"prompt": "

$\\frac{\\var{num11} - \\var{num12}}{\\var{num13} + \\var{num14}}$

\n

Estimate:      [[0]]

\n

Actual:          [[1]]

\n

% Error:        [[2]]%

", "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "gaps": [{"allowFractions": false, "variableReplacements": [], "maxValue": "{ans41}", "minValue": "{ans41}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"allowFractions": false, "variableReplacements": [], "maxValue": "{ans42}", "minValue": "{ans42}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"precisionType": "dp", "precisionMessage": "You have not given your answer to the correct precision.", "allowFractions": false, "variableReplacements": [], "maxValue": "{ans43}+1", "strictPrecision": false, "minValue": "{ans43}-1", "variableReplacementStrategy": "originalfirst", "precisionPartialCredit": 0, "correctAnswerFraction": false, "showCorrectAnswer": true, "precision": "1", "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}], "showCorrectAnswer": true, "scripts": {}, "marks": 0, "type": "gapfill"}, {"prompt": "

$\\frac{\\var{num15} - \\var{num16}}{\\var{num17} + \\var{num18}}$

\n

Estimate:      [[0]]

\n

Actual:          [[1]]

\n

% Error:        [[2]]%

", "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "gaps": [{"allowFractions": false, "variableReplacements": [], "maxValue": "{ans51}", "minValue": "{ans51}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"allowFractions": false, "variableReplacements": [], "maxValue": "{ans52}", "minValue": "{ans52}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"precisionType": "dp", "precisionMessage": "You have not given your answer to the correct precision.", "allowFractions": false, "variableReplacements": [], "maxValue": "{ans53}+1", "strictPrecision": false, "minValue": "{ans53}-1", "variableReplacementStrategy": "originalfirst", "precisionPartialCredit": 0, "correctAnswerFraction": false, "showCorrectAnswer": true, "precision": "1", "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}], "showCorrectAnswer": true, "scripts": {}, "marks": 0, "type": "gapfill"}, {"prompt": "

$\\frac{\\var{num19}^2 \\times \\var{num20}}{\\var{num21}}$

\n

Estimate:      [[0]]

\n

Actual:          [[1]]

\n

% Error:        [[2]]%

", "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "gaps": [{"allowFractions": false, "variableReplacements": [], "maxValue": "{ans61}", "minValue": "{ans61}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"allowFractions": false, "variableReplacements": [], "maxValue": "{ans62}", "minValue": "{ans62}", "variableReplacementStrategy": "originalfirst", "correctAnswerFraction": false, "showCorrectAnswer": true, "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}, {"precisionType": "dp", "precisionMessage": "You have not given your answer to the correct precision.", "allowFractions": false, "variableReplacements": [], "maxValue": "{ans63}+1", "strictPrecision": false, "minValue": "{ans63}-1", "variableReplacementStrategy": "originalfirst", "precisionPartialCredit": 0, "correctAnswerFraction": false, "showCorrectAnswer": true, "precision": "1", "scripts": {}, "marks": 1, "type": "numberentry", "showPrecisionHint": false}], "showCorrectAnswer": true, "scripts": {}, "marks": 0, "type": "gapfill"}], "extensions": [], "statement": "

By rounding each number correct to one significant figure, estimate the answer to each of the problems given below. Then use your calculator to accurately evaluate each of them.

\n

Calculate the percentage error in using the estimate, correct to one decimal place.

\n

 

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ans42)/ ans42)*100", "templateType": "anything", "group": "Ungrouped variables", "name": "ans43", "description": ""}, "ans42": {"definition": "(num11-num12)/(num13+num14)", "templateType": "anything", "group": "Ungrouped variables", "name": "ans42", "description": ""}, "num21": {"definition": "random(800.1..899#0.2)", "templateType": "anything", "group": "Ungrouped variables", "name": "num21", "description": ""}, "num20": {"definition": "tens()", "templateType": "anything", "group": "Ungrouped variables", "name": "num20", "description": ""}, "ans12": {"definition": "(num1*num2)/(num3*num4)", "templateType": "anything", "group": "Ungrouped variables", "name": "ans12", "description": ""}, "ans13": {"definition": "(abs(ans11 - ans12)/ ans12)*100", "templateType": "anything", "group": "Ungrouped variables", "name": "ans13", "description": ""}, "ans11": {"definition": "(siground(num1,1)*siground(num2,1))/(siground(num3,1)*siground(num4,1))", "templateType": "anything", "group": "Ungrouped variables", "name": "ans11", "description": ""}, "ans31": {"definition": "(siground(num8,1)*siground(num9,1))/siground(num10,1)", "templateType": "anything", "group": "Ungrouped variables", "name": "ans31", "description": ""}, "ans32": {"definition": "(num8*num9)/(num10)", "templateType": "anything", "group": "Ungrouped variables", "name": "ans32", "description": ""}, "ans33": {"definition": "(abs(ans31 - ans32)/ ans32)*100", "templateType": "anything", "group": "Ungrouped variables", "name": "ans33", "description": ""}, "ans52": {"definition": "(num15-num16)/(num17+num18)", "templateType": "anything", "group": "Ungrouped variables", "name": "ans52", "description": ""}, "ans53": {"definition": "(abs(ans51 - ans52)/ ans52)*100", "templateType": "anything", "group": "Ungrouped variables", "name": "ans53", "description": ""}, "ans51": {"definition": "(siground(num15,1)-siground(num16,1))/(siground(num17,1)+siground(num18,1))", "templateType": "anything", "group": "Ungrouped variables", "name": "ans51", "description": ""}, "num16": {"definition": "random(201..299)", "templateType": "anything", "group": "Ungrouped variables", "name": "num16", "description": ""}, "num17": {"definition": "random(41..59 except 50)", "templateType": "anything", "group": "Ungrouped variables", "name": "num17", "description": ""}, "num14": {"definition": "random(11..25#0.01 except num11)", "templateType": "anything", "group": "Ungrouped variables", "name": "num14", "description": ""}, "num15": {"definition": "hun()", "templateType": "anything", "group": "Ungrouped variables", "name": "num15", "description": ""}, "num12": {"definition": "sin()", "templateType": "anything", "group": "Ungrouped variables", "name": "num12", "description": ""}, "num13": {"definition": "random(3.5..5.5#0.01 except num12)", "templateType": "anything", "group": "Ungrouped variables", "name": "num13", "description": ""}, "num10": {"definition": "random(15..30#0.1 except num8)", "templateType": "anything", "group": "Ungrouped variables", "name": "num10", "description": ""}, "num11": {"definition": "precround(tens(),1)", "templateType": "anything", "group": "Ungrouped variables", "name": "num11", "description": ""}, "num18": {"definition": "random(201..299 except num16)", "templateType": "anything", "group": "Ungrouped variables", "name": "num18", "description": ""}, "num19": {"definition": "sin()", "templateType": "anything", "group": "Ungrouped variables", "name": "num19", "description": ""}}, "metadata": {"description": "

(Calculate the estimate, actual and from these the percentage error)

\n

rebelmaths

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