400 should be the answer. Hope this helps!
3(.80)+1.20= 3.60
3.60+1.40= 5
Annette gave the clerk $5
The given inequality is:

This inequality can be divided in two parts as:
a)

b)

Solving part a:

Solving part b:

Therefore, the solution to the given inequality is

and

. Combining both the ranges we get the solution:

.
In interval notation, this solution can be expressed as [1,5]