Pre Algebra
 by: Dr. Neven Jurkovic

Pre algebra is the subject you need to understand before moving on to learn algebra. In other terms, you can 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 know:

Negative numbers

Learn basic facts of adding, subtracting or multiplying negative numbers. For example, always remember:

• If both numbers have the same sign, the product is positive.
• If the numbers have different signs, the product 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 product.

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 can 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.