What is the cost of 1 gallon of oil before the tax is added?

Firstly, let's assume that the cost of 200 gallons of oil was x before the tax was added. So:

Before the tax was added, the cost of 200 gallons was $394. Now let's find the cost of one gallon of oil.


Thus, the cost of one gallon of oil before the tax was added is $1.97

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