Answer:
Let's solve first the part B.
We know that the company does not charge an extra fee is the luggage is less than 55 pounds.
Then if p represents the weight of the passenger's luggage, we need to have:
p is smaller than 55 lb
We also can write this as:
p < 55lb
where the symbol "<"
means that the left side is strictly smaller than the right side.
If we want to be more precise in the notation, we also should have a lower limit.
0lb < p < 55lb
Where the lower limit is because the weight of the luggage can not be zero or smaller than zero.
This is the inequality we wanted.
Now, how we represent this on a number line?
when we have:
x > a
We represent this with a open circle at x = a (this means that x = a is not a solution) and we draw an arrow to the right of a.
and for:
x < a
we represent this with an open circle at a, and we draw an arrow to the left of a.
And if we have:
a < x < b
we draw an open circle at x = a and another at x = b, and all the points between these circles will be solutions.
You can see the graph of the inequality below.
Part A)
(where the point of the arrow should not be there, and both circles should be white)