Final answer:
A flat income tax maintains the same rate despite income increases.
Step-by-step explanation:
The type of tax that maintains the same rate even if a person's income increases is known as a Flat income tax. With this type of tax, everyone pays the same percentage of their income regardless of how much they earn. For example, if the flat income tax rate is 10%, a person earning $10,000 would pay $1,000 in taxes, and a person earning $100,000 would pay $10,000 in taxes.
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