Exploring Divisibility, Multiples, Factors, and Primes

The video tutorial covers the concepts of divisibility, multiples, factors, and prime numbers. It explains the rules for determining if a number is divisible by another, using examples for numbers 1 through 10. The tutorial also introduces the concepts of multiples and factors, and defines prime and composite numbers, providing examples to illustrate each concept.

Which of the following numbers is divisible by 2?

• 513

• 123

• 216

• 315

To check if a number is divisible by 3, you need to:

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

• Double the last digit

• Check if it ends in 3

• Check if it ends in 0

A number is divisible by 4 if:

• It ends in 0 or 5

• The last two digits form a number divisible by 4

• The sum of its digits is divisible by 4

• It ends in 4

Which of the following numbers is divisible by 5?

• 123

• 175

• 312

• 207

For a number to be divisible by 6, it must be divisible by:

• 5 and 6

• 2 and 3

• 3 and 4

• 4 and 5

To check if a number is divisible by 7, you need to:

• Check if it ends in 7

• Double the last digit and subtract it from the rest of the number

• Add all the digits and see if the sum is divisible by 7

• Divide the number by 2 three times

A number is divisible by 10 if it:

• Is odd

• Ends in 0

• Ends in 5

• Is even

Multiples of a number are obtained by:

• Adding the number to itself

• Subtracting the number from itself

• Dividing the number by integers

• Multiplying the number by integers

Factors of a number are:

• Numbers that are prime

• Numbers that are multiples of the given number

• Numbers that can divide the given number without leaving a remainder

• Numbers that can be divided by the given number

A prime number is defined as:

• A number that is divisible by 2

• A number that has only two factors: 1 and itself

• A number that ends in 0

• A number that is a multiple of 3