Answer:
30 units.
Step-by-step explanation:
Let x be number of milk units sold.
It has been given that You begin the week with 20 units of milk. You purchase 40 units. Therefore, total units of milk will be [tex]20+40=60[/tex] units.
It has been given that your ending inventory for the week is 30 units, which means after selling x units from 60 units you are left with 30 units.
We can set this information in an equation as:
[tex]60-x=30[/tex]
[tex]-x=30-60[/tex]
[tex]-x=-30[/tex]
[tex]x=30[/tex]
Therefore, you have sold 30 units.
