Question 1112435
(Decimal point in Jada's purchase was left out but I put it in.)



m, price of Marker
p, price of Pen


{{{system(4m+5p=6.71,5m+3p=7.12)}}}



This step may prepare for elimination method:
{{{system(3(4m+5p)=3*6.71,5(5m+3p)=5*7.12)}}}

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