Explanation:
In arithmetic and number
theory, the least common
multiple (also called the lowest common multiple or smallest
common multiple) of two integers a and b,
usually denoted by LCM (a, b),
is the smallest positive integer that is a multiple of both a and b. (Our solved example in mathguru.com uses this concept)
It is familiar from grade-school arithmetic as the "lowest
common denominator" that must be determined before two fractions can be
added.
If either a or b is 0, LCM (a, b) is
defined to be zero.
The LCM of more than two integers or rational numbers is
well-defined: it is the smallest number that is an integer multiple of each of
them.
Example
What is the LCM of 4 and 6?
Multiples of 4 are:
4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44,
48, 52, 56, 60, 64, 68, 72, 76...
and the multiples of 6 are:
6, 12, 18, 24, 30, 36, 42, 48, 54, 60,
66, 72, ...
Common multiples of
4 and 6 are simply the numbers that are in both lists:
12, 24, 36, 48, 60, 72, ....
So the least common multiple of
4 and 6 is the smallest one of those: 12 (Our solved example in
mathguru.com uses this concept)
http://en.wikipedia.org/wiki/Least_common_multiple
Equation
An equation is a mathematical statement that
asserts the equality of two expressions. Equations consist of the expressions that have to be equal on
opposite sides of an equal sign, as in
Properties
If an equation in algebra is known to be true, the following operations may be used to
produce another true equation:
1. Any
real number can be added to both sides.
2. Any
real number can be subtracted from both sides.
3. Any
real number can be multiplied to both sides.
4. Any
non-zero real number can divide both sides. (Our
solved example in mathguru.com uses this concept)
http://en.wikipedia.org/wiki/Equation
The above explanation is copied from
Wikipedia, the free encyclopedia and is remixed as allowed under the Creative
Commons Attribution- ShareAlike 3.0 Unported License.