Fractions of an unknown amount - fast math trick

TL;DR

Learn how to find fractions of an unknown number by understanding the dividing and multiplying elements of fractions.

Transcript

good day welcome to the tech math Channel what we're going to be having a look at in this video is we're going to be looking how to work out fractions of an unknown number it's a fairly simple sort of thing to do once you get the hang of it the type of question we're going to be having a look at are ones like this okay so say you were asked 34 of w... Read More

Key Insights

• 👥 Fractions have a dividing element (denominator) and a multiplying element (numerator), representing divisions and groups, respectively.
• 🪡 To find fractions of an unknown number, the dividing and multiplying elements of the fraction need to be reversed.
• 👻 Reversing the dividing and multiplying elements allows us to isolate the unknown number.
• #️⃣ It is sometimes easier to work with smaller numbers when finding fractions of an unknown number.
• 🗂️ The same result can be achieved by multiplying the unknown number and then dividing or dividing the unknown number and then multiplying.
• ❓ Understanding the basics of fractions is essential for solving problems involving fractions.
• 💦 Working with fractions of an unknown number is a straightforward process once the concept is understood.

Questions & Answers

Q: How can we understand fractions better?

Fractions have a numerator (top part) representing the number of groups and a denominator (bottom part) representing the number of divisions. For example, 3/4 means dividing something into four equal parts and taking three of those parts.

Q: How do we find fractions of an unknown number?

To find a fraction of an unknown number, reverse the dividing and multiplying elements of the fraction. For example, to find 3/4 of a number equal to 12, divide 12 by 3 and then multiply by 4. The answer is 16.

Q: Can you explain finding fractions of an unknown number using another example?

Sure. Let's find 2/5 of an unknown number equaling 18. In this case, we divide 18 by 2 and multiply the result by 5. The answer is 45.

Q: Is there an alternative method to find fractions of an unknown number?

Yes, you can also multiply the unknown number by the multiplying element of the fraction and then divide by the dividing element. For example, to find 58 of an unknown number equal to 35, you can multiply 35 by 8 and then divide by 5. The answer is 56.

Summary & Key Takeaways

• The video explains how to work out fractions of an unknown number, using examples such as finding 3/4 of a number equal to 12.

• It emphasizes understanding the numerator and denominator of fractions, where the denominator represents the number of divisions and the numerator represents the number of groups.

• To isolate the unknown number, the video explains that the dividing and multiplying elements of the fraction need to be reversed.