Fiona is studying how income taxes impact various families and their finances. She creates a table with various amounts of taxes owed and estimates that this represents 9% of each family’s gross income.

Using proportions, it is found that the values that complete the table, from top to bottom, are given by: $670, $920, $1500, $2100.
A proportion is a fraction of a total amount.
Considering that the amounts in taxes correspond to 9% of the gross income, we have that for each family, we will find the incomes as follows:
Family 1:
0.09I = 60.30.
I = 60.30/0.09
I = $670.
Family 2:
0.09I = 82.80.
I = 82.80/0.09
I = $920.
Family 3:
0.09I = 135.00.
I = 135.00/0.09
I = $1500.
Family 4:
0.09I = 189.00.
I = 189.00/0.09
I = $2100.
More can be learned about proportions at https://brainly.com/question/24372153