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Used for LANTITE preparation (Australia). NC = Non Calculator strand. NA = Number & Algebra strand. Students are given the gifted proportion as a decimal, and the proportion of those who receive support as a decimal, and are required to find the proportion of the whole school who are gifted but do not receive support (as a decimal). There are 9 versions of this question.
", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "\n\nThe proportion of students at {school} school who have been identified as being gifted is {dec1}.
\nHowever, only {dec2} of those students receive additional support in the classroom.
", "advice": "\n{dec2} of the students identified as being gifted at {school} school receive additional support in the classroom.
\nTherefore, 1 - {dec2} = {1-dec2} of the students that are identified as being gifted do NOT receive additional support in the classroom.
\nSo, {1-dec2} of the students that are gifted do NOT receive additional support in the classroom, and the students identified as being gifted are {dec1} of the whole school population.
\nWe need to find {1-dec2} of {dec1}.
\nTo find a proportion of a proportion, we multiply.
\nWe need to evaluate {1-dec2} x {dec1}.
\nTo multiply decimals without a calculator, you could convert each decimal to a fraction, then multiply, then convert back to a decimal:
\n{1-dec2} x {dec1} = $\\frac {\\var{10-num2}} {10} \\times \\frac {\\var{num1}} {10} = \\frac {\\var{(10-num2)*num1}} {100}$ = {(10-num2)*num1/100}
\nAlternatively, multiply the numbers (ignoring decimal points), then count the total number of decimal places in the question. Put the decimal point back in, ensuring that the answer has this same number of decimal places.
\n{10-num2} x {num1} = {num1*(10-num2)}. There are two digits after the decimal point in the question (two decimal places in the question), so the answer requires two digits after the decimal point.
\n{1-dec2} x {dec1} = {(1-dec2)*dec1}
\nThe proportion of all students at {school} school who have been identified as being gifted, but do not receive additional support in the classroom is {(1-dec2)*dec1}.
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", "templateType": "anything"}, "num2": {"name": "num2", "group": "Ungrouped variables", "definition": "dec2*10", "description": "The numerator for dec2.
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