Worksheet on Increase and Decrease Percentage helps the students and the people who are preparing for various types of competitive tests. In this worksheet, we will discuss about how to calculate the Increase and Decrease percentage of the number. Let’s see how to calculate the percent in the below sections. Practice the Solved Examples listed below and get to know how to find Percentage Increase or Decrease easily.
How to Calculate PercentageIncrease and Decrease?
Increase Percentage:
To calculate Increase Percentage, we will subtract the new number from the original number by using the formula
Increase = New number – Original number. We will calculate the % Increase by using the formula
% Increase = increased value / original number — 100
Then, we will divide the result by the original number, after that we will convert the result we got into a percentage, by multiplying the result by 100.
In the below sections, you can see some of the solved examples on Increase Percentage.
Decrease Percentage:
To calculate Decrease Percentage, we will subtract the new number from the original number by using the formula.
Decrease Percentage = Original number – New number.
After that, we will divide the decrease by the original number, and we will multiply the answer by 100. To find the % Decrease, we will use the formula,
% Decrease = Decreased Value / original number — 100.
Below you can see some solved examples on Decrease percentage.
1. Solve the given below and find the Increased or Decreased number:
(i) 115 increased by 15%
(ii) 2500 increased by 10%
(iii) 380 decreased by 19%
(iv) 180 decreased by 24%
Solution:
(i) 115 increased by 15%
The given value is 115 by 15%,
As the number 115 was increased by 15%,
So, first, we will find the new number,
As a new number= 115 + increased percentage,
which means
= 115 + (15% —115)
on solving we will get 132.25.
So, the increased number is 132.25.
(ii) 2500 increased by 10%
The given value is 2500 by 10%,
As the number 2500 was increased by 10%,
So, first, we will find the new number,
As a new number= 2500 + increased percentage,
which means
= 2500 + (10% —2500)
on solving we will get 2,750.
So, the increased number is 2,750
(i) 380 decreased by 19%
The given value is 380 by 19%,
As the number 380 was decreased by 19%,
So, first, we will find the new number,
As a new number= 380 – decreased percentage,
which means
= 380 – (19% —380)
on solving we will get 307.8.
So, the number 380 decreases to 307.8.
(iv) 180 decreased by 24%
The given value is 180 by 24%,
As the number 180 was decreased by 24%,
So, first, we will find the new number,
As a new number= 180 – decreased percentage,
which means
= 180 – (24% —180)
on solving we will get 136.8.
So, the number decreases to 136.8.
2. Find the change in Percentage from the first quantity to the second quantity:
(i) 90 cm, 60 cm.
(ii) $650, $520.
(iii) 250 km, 450 km.
(iv) 50 km, 70km.
Solution:
(i) 90 cm, 60 cm.
Given 90 cm decreases to 60 cm,
so Decrease= Original number – New number.
= 90-60
which is 30,
Percentage of Decrease= Decrease / original number — 100
= 30/90 — 100
on solving, we will get 33.33%.
The decrease percent is 33.33%.
(ii) $520, $650.
Given $520 increases to $650.
Increase = New number – Original number
so Increase= $650-$520
which is 130,
Percentage of Increase= Increase / original number — 100
= 130/520 — 100
on solving, we will get 25%.
The Increase percent is 25%.
(iii) 300 km, 250 km.
Given 300 km decreases to 250 km,
so Decrease= Original number – New number.
= 300-250
which is 50,
Percentage of Decrease= Decrease / original number — 100
= 50/300 — 100
on solving, we will get 16.67%.
The decrease percent is 16.67%.
(iv) 50 km, 70km.
Given 50 km increases to 70 km,
Increase = New number – Original number
so Increase= 70-50
which is 20,
Percentage of Increase= Increase / original number — 100
= 20/50 — 100
on solving, we will get 40%.
The Increase percent is 40%.
3. The number 800 Increases by 20 % and then the number was decreased the same by 25 %. What is the new number in that case?
Solution:
Here, we must find the Increase number,
The given value is 800 increases by 20%,
which means
= 800 + (20% —800)
on solving we will get 960.
And 960 was decreased by 25%,
Which means
= 960 – (25% — 960)
On solving, we will get 720.
The new number is 720.
4. The total number of hours Maddy worked in the month of June is 32 hours, and in July he worked for 48 hours. Find by what percentage did Maddy’s work hours increases in July?
Solution:
Here, we will find the difference between hours of June and July,
which means 48 – 32= 16 hours.
now, we will find the increased percent,
Percentage of Increase= Increase / original number — 100
= 16/32 — 100
on solving, we will get 50%
So, the increase percent of Maddy’s working hours is 50%.
5. The total number of students in class 8 is 95 and in that 65 students went to the picnic. What is the decrease percentage?
Solution:
First, we will find the decreased number 95 – 65= 30,
then we will find the % of the decrease by using the formula
%Decrease = Decrease / original number — 100
= 30/95 —100
on solving, we will get 31.57%
So, the Decrease in percentage is 31.57%.