Key Concepts
• Determine the percentage of a given objective presence within a group of 100 objects.
• Convert the percentage into a decimal.
• Determine how much something will cost if it is discounted by a given percentage.
• Use a model to represent problems involving percent
Introduction:
If we are trying to find m percent of x, we can estimate this percent using the following steps:
- Here we round up or down to both numbers to some close numbers, which makes the calculation easier.
- Multiply the rounded numbers together.
- Divide the result by 100.
This is actually perfect for when you are dining because you can round up or down based on the level of service you receive.
Let’s suppose that when you and your friend have dinner. You both decided the service was good, so when you round your 18%, you decide to round up to 20% since 20 is an easy number to work with. You also have to round your $52.74. Since this is very close to $50, and 50 is easy to work with, you round to $50.
The next step is to multiply 20 by 50.
20 × 50 = 1000
Lastly, we divide the result by 100
= 1000/100
= 10
We see that when we estimate 18% of $52.74, we get $10.00, which is pretty close to the exact answer.
Let’s understand to Find the Percent of Number.
Here, we have two major methods to find the percent of the whole number.
Double line graph method
Using decimal method
Method 1:
Use a double line diagram and benchmark fraction equivalent to Estimate Percent
Example 1: Find 26% of 875.

Solution:
26% ≈ 25 %
And 875 ≈ 900
Now =
25100×25100×
900
=
14×14×
900
= 225
Method 2:
Use the decimal form to find the percent of the whole number
Example 1: Find 20% of 200.
Solution:

= 0.2 × 200
= 40
Example 2: Find 15% of 60.
Solution:

= 0.15 × 60
= 9
Example3: Find 40% of 450.
Solution:
Quantity = 450, Percentage = 40%
Step 1 =
20100
Step 2 =
2010020100
×× 650
= 2
××
65

= 130
More Word Problems: Understand Percent
Example 1: Sophia saves 40% of her monthly income. If her monthly income is $35,500, how much money does she save every month?
Solution: Monthly income of Sophia = $ 35,500
So, monthly saving of Sophia = 40% of $35500
=
4010040100
×× 35500
=
40× 35540× 355
=
1420014200
Example 2: A baseball pitcher won 80% of the games he pitched. If he pitched 35 ballgames, how many games did he win?

Solution:
First, we multiply 80 by 35
= 80 × 35
= 2800
Now, divide 2800 by 100 =
28001002800100
= 28
So, he played 28 games out of 35.
What have we learned:
• Determine the percentage of a given objective presence within a group of 100 objects.
• Convert the percentage into a decimal.
• Convert the percentage into a fraction.
• Determine how much something will cost if it is discounted by a given percentage.
• Use a model to represent problems involving percent.
Related topics
Composite Figures – Area and Volume
A composite figure is made up of simple geometric shapes. It is a 2-dimensional figure of basic two-dimensional shapes such as squares, triangles, rectangles, circles, etc. There are various shapes whose areas are different from one another. Everything has an area they occupy, from the laptop to your book. To understand the dynamics of composite […]
Read More >>Special Right Triangles: Types, Formulas, with Solved Examples.
Learn all about special right triangles- their types, formulas, and examples explained in detail for a better understanding. What are the shortcut ratios for the side lengths of special right triangles 30 60 90 and 45 45 90? How are these ratios related to the Pythagorean theorem? Right Angle Triangles A triangle with a ninety-degree […]
Read More >>Ways to Simplify Algebraic Expressions
Simplify algebraic expressions in Mathematics is a collection of various numeric expressions that multiple philosophers and historians have brought down. Talking of algebra, this branch of mathematics deals with the oldest concepts of mathematical sciences, geometry, and number theory. It is one of the earliest branches in the history of mathematics. The study of mathematical […]
Read More >>How to Solve Right Triangles?
In this article, we’ll learn about how to Solve Right Triangles. But first, learn about the Triangles. Triangles are made up of three line segments. These three segments meet to form three angles. The lengths of the sides and sizes of the angles are related to one another. If you know the size (length) of […]
Read More >>Other topics

Comments: