// Numbas version: finer_feedback_settings {"name": "39.h Two substitutions with fractions", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "39.h Two substitutions with fractions", "tags": [], "metadata": {"description": "
Substituting a values of $x$ and $z$ into $\\frac{ax+bz}{c}$
", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "If $\\var{Var1}=\\var{Var1Sub}$ and $\\var{Var2}=\\var{Var2Sub}$, find the value of
\n\\[\\simplify[basic]{({Num1}{Var1}+{Num2}{Var2})/{Num3}}.\\]
", "advice": "To substitute a variable for a number we just replace the letter in the equation with the number it is equal to. In this case since $\\var{Var1}=\\var{Var1Sub}$ and $\\var{Var2}=\\var{Var2Sub}$ we get
\n\\[\\simplify[basic]{({Num1}{Var1}+{Num2}{Var2})/{Num3}}=\\simplify[basic]{({Num1}{Var1Sub}+{Num2}{Var2Sub})/{Num3}}=\\simplify[basic]{({Num1*Var1Sub}+{Num2*Var2Sub})/{Num3}}=\\simplify[basic]{({Num1*Var1Sub+Num2*Var2Sub})/{Num3}}=\\var{(Num1*Var1Sub+Num2*Var2Sub)/Num3}.\\]
\n\nUse this link to find resources to help you revise substitution into a formula
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