Answer:
They sold 18 cookies every day.
Step-by-step explanation:
They sold 54 cookies in 3 days. To get how many they sold in one day, you have to divided 54 by 3 which is 18 cookies per day for the two of them.
Total cookies:-
[tex]\\ \sf\longmapsto 54(3)[/tex]
[tex]\\ \sf\longmapsto 162[/tex]