Understanding Percentages and Their Applications

In this video tutorial, Vitória Oliveira from Descomplica's math team explains how to calculate percentages, a common topic in math exams. The video covers the definition and representation of percentages, methods to calculate them, and the application of the rule of three. It also discusses practical applications in exams, such as calculating increases and discounts, and provides examples to illustrate these concepts. The video concludes with a reminder to download the mental map and check the description for additional resources.

Why is it important to learn about percentages?

• They are not commonly used in real life.

• They are only used in mathematics.

• They are only important for business studies.

• They are used in various exact sciences questions.

Which of the following is NOT a way to represent a percentage?

• As a fraction

• As a decimal number

• As a whole number

• Using the percentage symbol

What does the 'of' in 'X percent of Y' signify?

• Division

• Multiplication

• Subtraction

• Addition

How would you calculate 15% of 60?

• By multiplying 15% by 60

• By dividing 60 by 15

• By adding 15 to 60

• By subtracting 15 from 60

What is the result of 15% of 60?

• 6

• 12

• 9

• 7.5

What is the rule of three used for in percentage calculations?

• To divide percentages

• To subtract percentages

• To add percentages

• To find the percentage of a value

In the rule of three, if 60 is 100%, what is 15%?

• 6

• 7.5

• 9

• 12

How do you calculate an increase of X% on an initial value?

• Subtract X% from the initial value

• Multiply the initial value by 1 + X%

• Multiply the initial value by X%

• Divide the initial value by 1 + X%

How do you calculate a discount of X% on an initial value?

• Multiply the initial value by 1 + X%

• Multiply the initial value by X%

• Divide the initial value by 1 - X%

• Multiply the initial value by 1 - X%

What is the value after a 15% increase on 60?

• 69

• 45

• 51

• 75