Pre Algebra
Pre algebra is the subject you absolutely need to understand before moving on to learn algebra. In other terms, you may say that pre algebra is the perfect platform from where you can move on to algebra. However, we will talk about pre algebra as a separate entity here. Let us have a look at the key topics of pre algebra you must understand :
Negative numbers
Learn basic facts of adding, subtracting or multiplying negative numbers. For example, always remember:
If both numbers have the identical sign, the item is positive.
If the numbers have different signs, the item is negative.
Adding odd and even numbers
Here, just remember:
Even Number + Even Number = Even Number.
Odd Number + Odd Number = Even Number.
Even Number + Odd Number = Odd Number
Decimal numbers
While adding or subtracting decimal numbers, always place the numbers so that the decimal points are vertically aligned.
For example, 6.231 + 0.044 = 6.275.
While multiplying decimal numbers, multiply like you multiply whole numbers. Then add the decimal places in both numbers to find the position of the decimal point in the item.
While dividing, move the decimal point in the divisor to the right as necessary to make the divisor a whole number. Then the decimal point in the dividend is moved to the right the same number of places. The decimal point in the answer is placed just above the decimal point in the dividend. These facts are vital in pre algebra.
Square Root
To learn square roots, remember the following formulas:
Every positive real number n has two square roots
Product Property: For all positive real numbers a and b,
Quotient Property: For all positive real numbers a and b,
Reducing to lowest factors
Divide the top and the bottom by the same prime numbers until no more common prime number might be found.
e.g, 24/36 =4/6=2/3
Converting mixed number to improper fraction
In this, remember the following formula:

Converting improper fraction to mixed number
Divide the denominator into the numerator. The whole part of the answer is the whole part of the mixed number. The remainder will be the numerator of the fraction of the mixed number.
Finally, just learn these topics and practice them as much as possible. With instant you will surely master pre algebra, which will lay a great foundation for your algebra classes.