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# Word Problems and Data Analysis: GED Test Prep (page 4)

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Updated on Mar 9, 2011

### Graphs and Tables

The GED Mathematics Exam will test your ability to analyze graphs and tables. It is important to read each graph or table very carefully before reading the question. This will help you to process the information that is presented. It is extremely important to read all of the information presented, paying special attention to headings and units of measure. Here is an overview of the types of graphs you will encounter:

• Circle graphs or pie charts
• This type of graph is representative of a whole and is usually divided into percentages. Each section of the chart represents a portion of the whole, and all of these sections added together will equal 100% of the whole.

• Bar graphs
• Bar graphs compare similar things with different length bars representing different values. Be sure to read all labels and legends, looking carefully at the base and sides of the graph to see what the bars are measuring and how much they are increasing or decreasing.

• Broken line graphs
• Broken line graphs illustrate a measurable change over time. If a line is slanted up, it represents an increase whereas a line sloping down represents a decrease. A flat line indicates no change as time elapses.

### Scientific Notation

Scientific notation is a method used by scientists to convert very large or very small numbers to more manageable ones. You will have to make a few conversions to scientific notation on the GED Mathematics Exam. Expressing answers in scientific notation involves moving the decimal point and multiplying by a power of ten.

Example

A space satellite travels 46,000,000 miles from the earth. What is the number in scientific notation?

Step 1: Starting at the decimal point to the right of the last zero, move the decimal point until only one digit remains to its left:

46,000,000 becomes 4.6.

Step 2: Count the number of places the decimal was moved left. In this example, the decimal point was moved 7 places, and express it as a power of 10: 107

Step 3: Express the full answer in scientific notation by multiplying the reduced answer from step 1 by 107:

4.6 × 107

Example

An amoeba is .000056 inch long. What is its length in scientific notation?

Step 1: Move the decimal point to the right until there is one digit other than zero to the left of the decimal.

.000056 becomes 5.6

Step 2: Count the number of places moved to the right—5.However, because the value of the number is being increased as it is expressed in scientific notation, it is written as a negative exponent. 10–5

Step 3: Express the full answer in scientific notation: .0000056 becomes 5.6 × 10–5