word problem workbench

Topic:
Algebra
. EXAMPLE PROBLEM Clara has 15 pieces of fruit - some are apples and some are oranges. Apples cost $0.2 each, oranges $0.5 each. The total value of Clara's fruit is $4.50. How many apples and how many oranges does Clara have? OBJECTS call Apples OBJECT1 call Oranges OBJECT2 ATTRIBUTE1 [e.g. number, value, weight, density,...] [in this example - Attribute1 is number] call number(object1) X call number(object2) Y Apples & Oranges are both what ? Class: Fruit call number(class) N1 ATTRIBUTE2 [e.g. number, value, weight, density,...] [in this example - Attribute2 is value] call value(object1) p call value(object2) q RELATION 1: number(object1) + number(object2) = number(class) = N1 X + Y = N1 RELATION 2: value(object1) x number(object1) + value(object2) x number(object2)=value(class)=N2 pX + qY = N2 Plot RELATION 1 and RELATION 2 - in the {attribute1, attribute2} plane - in this example {number,value} plane - in the {object1, object2} plane - in this example {apples, oranges} plane [see other examples in Modeling & Formulating section of MathMindHabits website]
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