Divisibility Rules for 2,3 and 5

The video tutorial explains the concept of divisibility and provides quick methods to determine if a whole number is divisible by 2, 3, or 5. For divisibility by 2, check if the last digit is even. For divisibility by 3, sum the digits and check if the sum is divisible by 3. For divisibility by 5, the last digit should be 0 or 5. Examples are provided for each rule to illustrate the concepts.

Which of the following numbers is divisible by 2?

• 357

• 482

• 199

• 563

How can you quickly determine if a number is divisible by 3?

• Check if the last digit is 3

• Add the digits and see if the sum is divisible by 3

• Divide the number by 3 and check for no remainder

• Check if the number ends in 0 or 5

Is the number 45 divisible by 3?

• No, because it ends in 5

• Yes, because it ends in 5

• No, because 4 + 5 = 9, which is not divisible by 3

• Yes, because 4 + 5 = 9, which is divisible by 3

What is the rule for determining if a number is divisible by 5?

• The number must end in 2 or 4

• The sum of the digits must be 5

• The number must be even

• The number must end in 0 or 5

Which of these numbers is not divisible by 5?

• 312

• 150

• 400

• 205