Question

Wendy is paid $9 per hour and plans to work between 20 and 25 hours per week.

Identify the independent and dependent quantity in the situation
find reasonable domain and range values

Answer 1

The independent (or constant) is Wendy's wage of $9/hr. The dependent (or variable) is how many hours she is working each week. 

Answer 2

In an experiment the quantity that are taken to obtain the other quantity is called independent quantity,

While, the other quantity is called dependent quantity,

Given situation,

Wendy is paid $9 per hour and plans to work between 20 and 25 hours per week.

That is, the paid amount depends upon the number of hours,

Thus, independent quantity is number of hours and dependent quantity is paid amount,

Now, domain is the set of all possible value of independent quantity while range is the set of all possible values of dependent quantity,

Here, hours are between 20 to 25,

So domain is [20, 25]

Now, paid amount for 20 hours = 20 × 9 = $ 180,

And, paid amount for 25 hours = 25 × 9 = $ 225

Hence, Range is [180, 225]