If Natasha has $60, which is 3 times as much money as Carla, Carla has $60/3=$<<60/3=20>>20
Together, Carla and Natasha have $20+$60=$<<20+60=80>>80
Carla has twice as much money as Cosima, meaning Cosima has $20/2=$10
Combined, the three have $10+$80=$<<10+80=90>>90
If they buy goods with the amount they have and sell at 7/5 of the buying price, the total amount of money they will get from selling the goods is 7/5*90=$<<7/5*90=126>>126
If they earn $126 from the sale of the goods they bought with the money they had, their profit is $126-$90=$<<126-90=36>>36
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