Finding Total Cost

Today's math lesson centered on adding sales tax or a tip. We looked at two ways to work through these problems:

Two Step Method:
1. Find the tax (or tip) by multiplying the base cost by the percentage changed to a decimal.
2. Add the tax to the base cost.

Example: What is the cost of a $25 item with 7% sales tax?
.. $25.00 * .07 = $1.75
.. $25.00 + $1.75 = $26.75

One Step Method:
1. Multiply the base cost by the total percent of the purchase by adding the extra percent to 100 percent converted to a decimal.

Example: What is the cost of a $25 item with 7% sales tax?
.. $25.00 * 1.07 = $26.75