Step-by-step explanation:
Let the total packing cost be [tex]p[/tex].
Let the total number of packages to be sold to to break be [tex]n[/tex].
Given that packaging cost for each packet is [tex]0.35[/tex]
So,[tex]p=0.35n[/tex].
Let the total income be [tex]pr[/tex]
Given that income of one packet is [tex]2.5[/tex]
So,[tex]pr=2.5n[/tex]
In addition,there is a fixed cost for the ingredients.
So,[tex]2.5n=0.35n+138[/tex]
[tex]2.15n=138\\n=64.18[/tex]
So,atleast [tex]65[/tex] packets has to be sold inorder to avoid losses.