Divisibility Rules and Basic Arithmetic

The video tutorial by Mr. J explains the divisibility rule for 12, which states that a number is divisible by 12 if it is divisible by both 3 and 4. The video provides four examples to demonstrate this rule. For each example, the sum of the digits is checked for divisibility by 3, and the last two digits are checked for divisibility by 4. The video concludes with a summary of the rule and its application.

What is the main condition for a number to be divisible by 12?

• It must be divisible by 5 and 10.

• It must be divisible by 2 and 6.

• It must be divisible by 3 and 4.

• It must be divisible by 7 and 8.

How do you determine if a number is divisible by 3?

• Check if the last digit is 0 or 5.

• Check if the number is a multiple of 10.

• Sum the digits and see if the sum is divisible by 3.

• Check if the number is even.

What is the rule for checking divisibility by 4?

• Check if the number ends in 0.

• Check if the last two digits form a number divisible by 4.

• Check if the number is a multiple of 5.

• Check if the number is even.

What is the sum of the digits of 648?

• 20

• 16

• 22

• 18

Is 648 divisible by 3?

• No, because it is not a multiple of 5.

• Yes, because it is an even number.

• Yes, because the sum of its digits is divisible by 3.

• No, because the sum of its digits is not divisible by 3.

What is the result of dividing 48 by 4?

• 11

• 12

• 10

• 13

What is the sum of the digits of 1,140?

• 5

• 6

• 7

• 8

Is 1,140 divisible by 3?

• Yes, because the sum of its digits is divisible by 3.

• No, because the sum of its digits is not divisible by 3.

• No, because it is not a multiple of 5.

• Yes, because it is an even number.

What is the result of dividing 40 by 4?

• 9

• 11

• 8

• 10

Is 1,140 divisible by 12?

• No, because it is not divisible by 5.

• Yes, because it is a multiple of 10.

• No, because it is not divisible by 3.

• Yes, because it is divisible by both 3 and 4.