GMAT Practice — Integrated Reasoning
Question 3 (below) refers to the following chart, which plots changes in average birth and mortality rates from one particular decade (1991-2000) to the next (2001-2010). Each symbol represents a different U.S. city.
Assume that birth and mortality rates were the only factors in each city's population change from one decade to the next. Use the drop-down menus to complete the following two statements according to the information presented in the chart.
The data suggest that from one decade to the next a total of cities in Group A experienced population declines.
Among the cities in Group B whose birth rates increased from one decade to the next, the median change in mortality rate was approximately percent.
This is a Graphics Interpretation question. To receive credit for a correct response you would need to choose both correct pull-down menu selections. (No partial credit would be awarded.)
First statement. The cities in Group A are represented by squares. Notice that any increase in mortality rate (plotted to the right of zero on the x-axis) is accompanied by either a smaller increase in birth rate or a decline in birth rate. Conversely, any decrease in mortality rate (plotted to the left of zero on the x-axis) is accompanied by a greater decrease in birth rate. Any of these three scenarios suggests a declining population for all nine cities in Group A — assuming that other factors remain constant. The correct selection for the first statement is nine.
Second statement. The cities in Group B are represented by triangles. The six triangles located in the chart's upper (white) portion are the ones whose birth rates increased. Among those six, the median position along the x-axis (i.e., mortality rate) is 0.2%, which is the average of 0.0% and +0.4% — the locations of the two middle-positioned triangles along the x-axis. The correct selection for the second statement is 0.2.