GRE General TestQuantitative ReasoningEasy
A technician is calibrating a sensor. The sensor's initial reading is 12 units. After calibration, the reading is 15 units. What is the percentage increase in the sensor's reading?
- A33.3%
- B30%
- C25%
- D20%
Show answer & explanationAnswer & explanation
Correct answer: C. 25%
The percentage increase is calculated by dividing the absolute increase by the original value and multiplying by 100. (15 - 12) / 12 = 3 / 12 = 0.25, which is 25%.
Why the other options are wrong
- A. This is a common miscalculation, possibly from dividing by the difference.
- B. This incorrectly calculates the increase relative to the new value or makes a calculation error.
- D. This would be the percentage decrease if the value went from 15 to 12.
Percentage Increase
A measure of the relative growth of a quantity, expressed as a percentage of the original quantity.
- Calculated as (New Value - Original Value) / Original Value * 100%
- Used to show how much a quantity has grown.
- Essential for analyzing growth rates in various fields.
Memory trick: New-Old over Old, then multiply by 100, the change is bold!