Lillian counted the number of push-ups she could complete while her friend timed her and recorded the data every 10 seconds. The independent variable is the amount of time that passed in seconds, written in the first column. The dependent variable is the number of push-ups Lillian completed, written in the second column. The more time Lillian was given, the more push-ups she could complete. The number of push-ups depends on the number of seconds.

Often, the data collected in a table or chart are used to generate a graph representing the same information. Visualizing the data can help to see patterns in the data.

Here is a graph of the same data represented in Lillian’s table:
Even though Lillian did not record the number of push-ups completed in 15 seconds, we can estimate how many she completed by looking at the graph. Locate 15 on the x-axis, and follow it up to the line. On the y-axis, the point is at approximately 6. This means Lillian probably completed 6 push-ups after 15 seconds.