Adding And Subtracting Standard Form Worksheet

Adding and subtracting standard form at a glance

Standard form, or standard index form, is a simple way of writing very large numbers or very small numbers. To convert numbers to standard form, we write them as decimals between 1 and 10, multiplied by a power of 10.  We call numbers that are not written in standard form ordinary numbers.

If we are adding or subtracting two standard form numbers with different powers of 10, the place value of the numbers written in the decimals will be different so we cannot add or subtract them directly. Therefore, when adding and subtracting numbers in standard form we first convert the numbers back to ordinary numbers. Once we have added or subtracted them, we can convert the answer back into standard form. 

Alternatively we can make the both powers of 10 the same by adjusting the number. Once the powers of 10 are the same we can then add or subtract the numbers, taking care to ensure the final answer is in standard form.

Looking forward, students can then progress to additional number worksheets, for example a fractions worksheet or a rounding worksheet.

For more teaching and learning support on Number our GCSE maths lessons provide step by step support for all GCSE maths concepts.