The sum of the ratios representing the amount of money the three has is 4+5+6=<<4+5+6=15>>15
If the total amount of money they have is $75, the amount of money Cara has represented by the fraction 4/15 is 4/15*$75=$<<4/15*75=20>>20
Similarly, the amount of money Janet has represented by the fraction 5/15 of the total ratio is 5/15*$75=$<<5/15*75=25>>25
Combined, Cara and Janet have $20+25=$<<20+25=45>>45
If Cara and Janet buy goods worth $45 and sells them at 80% of the buying price, the selling price of the goods will be 80/100*$45=$<<45*80/100=36>>36
Since they bought the goods at $45 and sold them at $36, Janet and Cara would run at a loss of $45-$36=$<<45-36=9>>9
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