Standard Form is a convenient method for writing out very large or very small numbers.

The general form is :

$ {\Large{N \times 10^n}} $

where 'N' is a number equal to, or more than one, but less than ten,

$ {\Large{ 1 \le N < 10}} $

and 'n' is the power to which 10 is raised.

Example #1 - What is 149550 in standard index form?

Take the first number(1) and place a decimal point after it. Continue writing down the other numbers behind. This is 'N'.

N = 1.49550

Now count the number of numerals there are after the decimal point.There are 5.This is our value for 'n' in the expression.

Therefore 149550 becomes

Example #2 - What is 0.0000218 in standard index form?

Write out the first number after the line of zeros(2), and place a decimal point after it. Continue writing down the other numbers behind. This is 'N'.

N = 2.18

Now count the number of zeros between the original decimal point and the first number(2).

Add '1'. This number gives you the value of 'n'. In this case 4+1=5.

But because we are dealing with a number less than one, the index 'n' is negative.

The index is '-5'.

0.0000218 becomes

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