Prime Numbers, Factors and Multiples - Revision Set

Odd number

A number that is NOT divisible by 2

Common factor

A number that is a factor of two or more numbers

Even number

A whole number ending with 0, 2, 4, 6, or 8 in the ones place. These numbers can be divided by 2 evenly and with no remainder.

Prime Numbers

Numbers divisible by ONLY two factors, which are: "1" and "itself". Examples: The SHADED numbers in the box. Example: 7 is only divisible by: { 1 and 7 }

Composite Numbers

Numbers divisible by three or more factors. Examples: The SHADED numbers in the box. Example: 4 is divisible by: { 1, 2, and 4 }

Factors

Numbers that can be divided into another number EVENLY. Example: The Factors of 12 are { 1, 2, 3, 4, 6, and 12 }. ALSO, Factors can be multiplied together to equal a Product or Multiple. Example: The Factor Pairs of 12 are { 1 x 12 }. { 2 x 6 }. { 3 x 4 }.

Multiples

Numbers you get when you multiply two numbers or factors together. Example: The multiples of 5 are: 5, 10, 15, 20, 25... Example: On your Time Table Chart look under the "5" Time Tables.

Highest Common Factor (HCF)

The largest factor that occurs in each of the sets of factors of a group of terms or expressions

Lowest Common Multiple (LCM)

The lowest number that will divide by all the numbers in question. To find- list all the prime factors of both numbers and multiply them all for the LCM.

EVEN Numbers

These numbers CAN BE divided by the number "2".

ODD Numbers

These numbers CANNOT be divided by the number "2".

"0" and "1".

These two numbers ARE NOT Prime and NOT Composite? They are called: "NEITHER"

The number "2"

This is the only EVEN Prime Number.

Factor Pairs

Two factors that are multiplied together to get a Product or Multiple.

Product

the answer to a multiplication problem