Maths Playing with Numbers part 6 (Divisibility Test : 2, 5, 10) CBSE Class 8 Mathematics VIII

TL;DR

In this video, the presenter discusses tricks for quickly determining if a number is divisible by 2, 5, or 10.

Transcript

hello friends this video on playing with numbers patch 6 is brought to you by example calm no more pure from exam ok so now that we learned about a few tricks of the puzzles it's time to talk about something different so now that we were talking about expanding numbers and doing all of their calculations do you remember that we had learned about th... Read More

Key Insights

• 👀 Divisibility by 2, 5, and 10 can be quickly determined by looking at the units place digit.
• 📏 These divisibility rules are derived from patterns observed in the multiples of 2, 5, and 10.
• 🪡 By using these rules, one can easily determine if a number is divisible by 2, 5, or 10 without the need for actual division.

Questions & Answers

Q: How can you determine if a number is divisible by 2 without actually dividing it?

To determine if a number is divisible by 2, you just need to look at the units place digit. If it is 0, 2, 4, 6, or 8, then the number is divisible by 2. This rule is derived from observing the pattern in the multiples of 2.

Q: What is the divisibility rule for numbers divisible by 5?

To determine if a number is divisible by 5, you just need to look at the units place digit. If it is 0 or 5, then the number is divisible by 5. This rule is derived from observing the pattern in the multiples of 5.

Q: How do you know if a number is divisible by 10?

A number is divisible by 10 if it ends with a 0. This rule is derived from observing the pattern in the multiples of 10, all of which end with a 0.

Q: Why do these divisibility rules work?

These rules are based on patterns observed in the multiples of 2, 5, and 10. By looking at these patterns, we can determine that if a number's units place digit matches the pattern (0, 2, 4, 6, 8 for 2; 0, 5 for 5; 0 for 10), then the number is divisible by that respective number.

Summary & Key Takeaways

• The video provides an overview of divisibility rules for numbers ending in 0, 2, 4, 6, 8 (divisible by 2), 0 or 5 (divisible by 5), and 0 (divisible by 10).

• The presenter explains that these rules are derived from observing the patterns in the multiples of 2, 5, and 10.

• By focusing only on the units place digit, one can quickly determine if a number is divisible by 2, 5, or 10 without the need for actual division.