Proportional Relationships and Time

This video tutorial covers the concept of Regra de Três Simples, focusing on directly and inversely proportional quantities. It begins with an introduction to grandezas, explaining what they are and providing examples. The tutorial then explores examples of direct and inverse proportionality, followed by a detailed explanation of Regra de Três Simples. Two problem-solving examples are provided: one involving direct proportionality and the other inverse proportionality, demonstrating how to apply the concepts in practical scenarios.

What is the Simple Rule of Three used for?

• To solve problems involving three or more quantities

• To measure the length of objects

• To solve problems involving two quantities that are either directly or inversely proportional

• To calculate the area of a square

Which of the following is NOT an example of a measurable quantity?

• Time

• Distance

• Happiness

• Volume

What is the relationship between speed and time if the speed increases?

• Time decreases

• Time doubles

• Time remains the same

• Time increases

If the distance increases, what happens to the time taken if the speed is constant?

• Time doubles

• Time decreases

• Time remains the same

• Time increases

What happens to the time taken to complete a task if the number of workers increases?

• Time doubles

• Time remains the same

• Time decreases

• Time increases

How are hours worked per day and time to complete a task related?

• Inversely proportional

• Exponentially related

• Directly proportional

• Not related

In a directly proportional relationship, if one quantity doubles, what happens to the other quantity?

• It remains the same

• It doubles

• It halves

• It triples

A gardener takes 15 hours to cut a lawn of 14,400 square meters. How long will it take to cut a lawn of 6,000 square meters?

• 8 hours

• 7 hours

• 6.25 hours

• 6 hours

If a farmer has enough feed for 100 pigs for 30 days, how long will the feed last if he buys 20 more pigs?

• 35 days

• 30 days

• 25 days

• 20 days

In an inversely proportional relationship, if one quantity triples, what happens to the other quantity?

• It remains the same

• It triples

• It halves

• It becomes one-third