Question 346704
let x=# of packages of cards bought
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given
80 cents each for some packages of cards
this means:  Cost=0.80*x
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She sold all but 18 packages for $2 each
This means:  sold x-18 at $2
Revenue=(x-18)*2  (she apparently kept 18 or gave them away for free)
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Profit=Revenue-cost 
48=(x-18)*2-0.08*x
48=2x-0.08x-36
48+36=1.2x
84/1.2=x
70=x
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validate
go back to original equation and substitute x=70
48=(x-18)*2-0.08*x
48=(70-18)*2-0.8*70=52*2-56=104-56=48
checked
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answer {{{highlight_green(70=x)}}}