# Standard form help. How to convert large numbers to standard index form.

Updated on August 5, 2013

Before I show you how to change a normal number into standard index form let me explain the definition of standard index form. Standard index form is a mathematical system of writing down small and large numbers. A number in standard index form will take the form m × 10n. m is a number which must be between 1 and 10 and n is the amount of times you multiply m by to give you the original number. Let’s take a look at a few examples of writing down large numbers in standard form.

Example 1

Write down 8 600 000 in standard form.

All you need to do is find the values of m and n.

m = 8.6 as m must be between 1 and 10.

n = 6 because you have to multiply 8.6 by 10 six times to give you 8 600 000.

So your answer is 8.6 × 10⁶.

Example 2

Write down 72 400 in standard form.

m = 7.24 as m must be between 1 and 10.

n = 4 because you have to multiply 7.24 four times to give you 72,400

So your answer is 7.24 × 10⁴

Example 3

Write 8 million in standard form.

First write down 8 million as 8 000 000.

Now m = 8 (or 8.0 if you prefer) as m must be between 1 and 10.

n = 6 because you have to multiply 8 six times to give 8 000 000.

So your answer is 8 × 10⁶.

Example 4

Write down 27 800 000 in standard form.

m = 2.78 as m must be between 1 and 10.

n = 7 because you have to multiply 2.78 seven times to give 27 800 000.

So your answer is 2.78 × 10⁷.

Example 5

Write down 8 753 865 974 in standard form.

Now in this case since there are several non zero digits so it will be appropriate to round your number to 3 significant figures before you put the number in standard index form. You do this because standard form is meant to be a quick way of writing down large numbers and it will be defeating the point if you make m = 8.753865974!

8 753 865 974 = 8 750 000 000 (3 s.f)

So m = 8.75 and n = 9.

So your answer will be 8.75 × 10⁹.

18

2

1

## Popular

10

59

• ### Financial Literacy for Kids Games & Websites

79

Submit a Comment

• AUTHOR

Mark

5 years ago from England, UK

Just corrected that mistake, thanks.

• A.

5 years ago

7.24x10^4 doesn't equal 8 600 000

• Ameya Vitankar

7 years ago

How do you change 30.7 in standard form?

• AUTHOR

Mark

7 years ago from England, UK

First round the number to 3 significant figures:

12,831,970 = 12,800,000 as you don't want all the non zero digits in the answer.

Now, write this is standard form:

= 1.28 x 10^7

• neiko

7 years ago

how do you write twelve million eight hundred thirty one thousand nine hundred seventy in standard form

working