Percentage Increase or Decrease: Percentage Increase or Decrease Examples

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Percentage Increase

When comparing the increase in a quantity over a period time, we first find the difference between the original value and the increased value. This difference is used to find the relative increase against the original value and express it in the terms of percentage. The formula for percentage increase is given by:

Percentage Decrease

When comparing the decrease in a quantity over a period of time, we first find the difference between the original value and the decreased value. We then use this difference to find the relative decrease against the original value and express it in the form of a percentage. The formula for percentage decrease is given by:

Percentage Increase or Decrease Examples

Example 1:

The annual salary of Suresh increased from . Find the percentage increase.

Solution:

• Original salary

• Increased salary

• Increase in salary

• We have formula to find out the percentage of increase.

• Percentage Increased

• Put the value in above formula

• First, we take the subtraction,

• Then take a division,

• So, Increased percentage is 25%.

Example 2:

The population of a small town decreased from due to breakout of an epidemic. What is the percentage decrease in the population?

Solution: Original population

Decreased population

Decrease in population

Percentage decrease in population

Example 3:

The number of people attending the first basketball game of the season was 840. The number of people attending the last basketball game of the season was 1200. What was the percent increase in attendance, to nearest percent?

Solution:

• Original Attendance

• Increased Attendance

• Increased Percentage