Explain when it is appropriate to use a benchmark percent in solving a problem.

These benchmark values are sometimes used when estimating a solution involving percentages. If an item costs $36.00 and there is a 7% sales tax, the benchmark of 10% can be used to mentally estimate the sales tax of the item. 10% of 36, done mentally, is 3.6.

The most common benchmarks are 10%, 25%, 50%, 75%, and 100%. These benchmark values are sometimes used when estimating a solution solving percentages

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