Tax as a Percentage of Total Amount

This item is taken from IGCSE Mathematics (0580) Paper 32 of May/June 2010.

To deal with this item, let us summarize the details of the problem:
   (a) Syllabus area: Algebra
   (b) Specific topic: Percentages
   (c) Formula Needed:

Let us recall that a tax is a financial charge or contribution imposed by the government on workers' income. The tax is deducted to the GROSS INCOME. After the tax is deducted, the worker will then receive the NET INCOME.

Let us use two methods in solving this problem.
First, 

And second is

Therefore, the tax is 12% of the total earnings of Francis.

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