### Featured GED Math Problem Video

GED® is a registered trademark of the American Council on Education (ACE) and administered exclusively by GED Testing Service LLC under license. This material [or content] is not endorsed or approved by ACE or GED Testing Service.

## Using Simple Interest to Determine Total Cost of Land

As defined by Merriam Webster, simple interest is the interest paid on the original principal only of a loan or on the amount of an account.

It is the fee that a person pays for the use of someone else’s money. This type of interest is called simple interest and there is a simple formula for finding it.

simple interest = principle x rate x time

This is an important GED math concept to understand and practice.  Be sure to always change the percent to a decimal before multiplying (i.e. 6% = .06).  Also remember that time is based on years. So, if the time is 2 years you multiply by 2, but if the time is 6 months you multiply by 6/12 or 0.5 because it is a half a year.

Simple Interest

## How Much Will It Cost To Fix Driveway

It is important that GED math students know how to determine cost using the cost formula c=nr.

Cost formula

total cost = (number of units ) x (price per unit)

It is also important to be able to use this formula to determine the number of units or the price per unit.

total cost / number of units = price per unit

total cost / price per unit = number of units

Because this formula can be used in a variety of ways, it is important that when you solve a GED math problem you read the problem carefully and substitute the values back into the formula.  Also be aware that if there is extra important information, you include that as well.

What better way to practice this formula than to show students a real life application.  Not everyone will need to fix their driveway, but it may apply to many students… especially those in rural areas were gravel driveways are popular.

fixing driveway

This problem will give students an opportunity to explore this cost formula as well as algebraically set this problem to be solved.

One could also explore the cost per gallon of gas, cost of a single egg in a dozen, or cost comparison when looking at meat at a grocery deli.

Whatever you choose, your students will benefit not just for the test… but for days months years to come.