Integers

• The HCF (Highest Common factor) is the largest common factor of two or more numbers. To find the HCF list all the factors of both numbers and find the largest one that both numbers have in common.
• The LCM (Lowest Common Multiple) of two numbers is the smallest number that is a common multiple of both numbers. To find the LCM list all the multiples of both numbers and find the smallest multiple that both numbers have in common.
• When dividing or multiplying negative and positive integers multiply or divide the numbers first and then if the signs are different or mixed the number will be negative and if they are the same they will be positive.
• When adding or subtracting negative and positive integers remember that if the signs are the same the number will positive. If they are not the same remember that when you subtract from a negative number the number decreases (although the number gets larger) away from zero. When you add to a negative number it increases (although the number gets smaller) towards zero.