Using proportions, considering the income tax of 10%, you actually earn $1,215 a month.
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
For people earnings less than $19,000 a year, the income tax is of 10%, hence the amount you actually earn is given by:
A = 0.9 x 1350 = $1,215 a month.
More can be learned about proportions at https://brainly.com/question/24372153
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