They had $80 saved up because 2 x 40 = <<2*40=80>>80
They spent $60 because 80 x (3/4) = <<80*(3/4)=60>>60
They had $20 left for ice cream because 80 - 60 = <<80-60=20>>20
They had $2 left after leaving the ice cream shop because 2 x 1 = <<2*1=2>>2
They spent $18 on ice cream because 20 - 2 = <<20-2=18>>18
The bought 12 scoops of ice cream because 18 / 1.5 = <<18/1.5=12>>12
The each bought 6 scoops because 12 / 2 = <<12/2=6>>6
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