Graphs offer a way to display data in an easy-to-understand format. However, it takes a little bit of reading between the lines sometimes to figure out what data the graph displays. One important component of any graph is its scale. You can see scales on both the horizontal and vertical axes of a graph, and they tell the reader how much or how many of a given unit is being measured. The interval of the scale represents the gap between one unit and the next.
Look carefully at the graph. Identify the x-axis and the y-axis. The x-axis runs vertically, meaning it goes from the bottom of the page to the top of the page. Its counterpart, the y-axis, runs horizontally, meaning it starts on the left-hand side of the page and continues to the right-hand side of the page. The two axes meet at the origin, which creates a 90-degree angle.
Place your finger on the first hash mark on the y-axis. Read the number below the hash mark. That number indicates the first interval. Move your finger to the next hasg mark. The number below the second hash mark represents the second interval. Subtract the first number from the second number, and the result will give you the amount of the interval.
Put your finger on the first hash mark on the x-axis. Look carefully at the number to the left of the hash mark. That number denotes the first interval on that axis. Slide your finger upward towards the next hash mark. The number to the left of the second hash mark equals the second interval. Once again, subtract the first number from the second number. The resulting figure will be the scale interval for the x-axis.