SOLUTION: a dealer buys 120 pens, x of them cost R3 each and the others cost R4 each. how do I express in terms of x the number of pens he buys for R4

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: a dealer buys 120 pens, x of them cost R3 each and the others cost R4 each. how do I express in terms of x the number of pens he buys for R4      Log On


   

Question 1025092: a dealer buys 120 pens, x of them cost R3 each and the others cost R4 each. how do I express in terms of x the number of pens he buys for R4
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The 2 groups of pens are:
+x+ pens
+120+-+x+ pens
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+3x+ is the cost of +x+ pens
+4%2A%28+120+-+x+%29+ is the cost of the remaining pens
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+3x+%2B+4%2A%28+120+-+x+%29+ is the total cost of all 120 pens