Standard Form

Key Facts and Exam Tips

A number in standard form always has a 'front' number, a multiplication sign, and a power of ten. The 'front' number is always greater than or equal to 1 and less than 10.

If the power is positive, the number is large. If the power is negative, the number is small.

When multiplying (or dividing) numbers in standard form, group the front numbers together and the powers of ten together. Multiply (or divide) the front numbers. Add (or subtract) the indices in the powers of ten.

Check that your result is in standard form. If it isn't, adjust the figures so that the front number is between 1 and 10.

If the question involves adding or subtracting numbers in standard form, you will need to convert them to ordinary decimal form, then do the calculation, and then convert the answer back into standard form.

Make sure you understand how your own calculator deals with very large and very small numbers. Can it show numbers in standard form (also called 'scientific' or 'exponential' notation), and if so, how? Find out how to read and enter numbers in standard form on your calculator.