GED Mathematical Reasoning TestAlgebraic Problem Solving with Graphs and FunctionsMedium
A meteorologist is tracking a weather balloon. The balloon's altitude, h(t), in meters, after t minutes, is given by the graph below. Based on the graph, what is the approximate altitude of the balloon after 30 minutes?
- A300 meters
- B350 meters
- C250 meters
- D200 meters
Show answer & explanationAnswer & explanation
Correct answer: C. 250 meters
To find the altitude at 30 minutes, locate '30' on the horizontal (time) axis, move vertically up to the graph line, and then horizontally across to the vertical (altitude) axis to read the corresponding value.
Why the other options are wrong
- A. This value is higher than the altitude at 30 minutes, likely reading from 40 minutes or misinterpreting the scale.
- B. This value is significantly higher, likely reading from 50 minutes or misinterpreting the scale.
- D. This value is lower than the altitude at 30 minutes, likely reading from 20 minutes or misinterpreting the scale.
Interpreting Graphs
Interpreting a graph involves extracting specific information by locating points, reading values from axes, and understanding the relationship between variables represented by the curve or line.
- Horizontal axis usually represents the independent variable (input).
- Vertical axis usually represents the dependent variable (output).
- To find output for a given input, locate input on horizontal axis, move to graph, then to vertical axis.
- To find input for a given output, locate output on vertical axis, move to graph, then to horizontal axis.
Memory trick: Axis, Line, Point – Information you've got!