Class 8 Exam  >  Class 8 Questions  >  A number is increased by 20% and then decreas... Start Learning for Free
A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.?
Most Upvoted Answer
A number is increased by 20% and then decreased by 20%. Find the net i...
Community Answer
A number is increased by 20% and then decreased by 20%. Find the net i...
Problem:
A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.

Solution:

To find the net increase or decrease percent, we need to understand the concept of percent increase and percent decrease.

Percent Increase:
When a number is increased by a certain percentage, the new value is calculated by adding the percentage increase to the original number.

Let's say the original number is x and the percentage increase is p.

The new value after a percent increase is calculated as:
New Value = x + (p/100) * x
= x * (1 + p/100)

Percent Decrease:
When a number is decreased by a certain percentage, the new value is calculated by subtracting the percentage decrease from the original number.

Let's say the original number is x and the percentage decrease is p.

The new value after a percent decrease is calculated as:
New Value = x - (p/100) * x
= x * (1 - p/100)

Given:
The number is increased by 20% and then decreased by 20%.

Step 1:
First, let's assume the original number as x.

Step 2:
The number is increased by 20%, which means the new value after an increase is:
New Value after increase = x * (1 + 20/100)
= x * (1 + 0.2)
= 1.2x

Step 3:
The number is then decreased by 20% from the increased value, which means the new value after a decrease is:
New Value after decrease = 1.2x * (1 - 20/100)
= 1.2x * (1 - 0.2)
= 1.2x * 0.8
= 0.96x

Step 4:
To find the net increase or decrease percent, we need to compare the final value with the original value.

The net increase or decrease percent can be calculated using the formula:
Net Increase or Decrease Percent = ((Final Value - Original Value) / Original Value) * 100

In this case,
Final Value = 0.96x
Original Value = x

Net Increase or Decrease Percent = ((0.96x - x) / x) * 100
= (-0.04x / x) * 100
= -4%

Therefore, the net increase or decrease percent is -4%.

Answer:
The net increase or decrease percent is -4%.
Attention Class 8 Students!
To make sure you are not studying endlessly, EduRev has designed Class 8 study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Class 8.
Explore Courses for Class 8 exam

Top Courses for Class 8

A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.?
Question Description
A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.? for Class 8 2024 is part of Class 8 preparation. The Question and answers have been prepared according to the Class 8 exam syllabus. Information about A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.? covers all topics & solutions for Class 8 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.?.
Solutions for A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.? in English & in Hindi are available as part of our courses for Class 8. Download more important topics, notes, lectures and mock test series for Class 8 Exam by signing up for free.
Here you can find the meaning of A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.? defined & explained in the simplest way possible. Besides giving the explanation of A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.?, a detailed solution for A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.? has been provided alongside types of A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.? theory, EduRev gives you an ample number of questions to practice A number is increased by 20% and then decreased by 20%. Find the net increase or decrease percent.? tests, examples and also practice Class 8 tests.
Explore Courses for Class 8 exam

Top Courses for Class 8

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev