Standard Form Calculations

In this video we are going to look at how to do calculations with standard form. When adding and subtracting numbers in standard form, we need to write the numbers out into ordinary numbers, do the sum and then turn the answer back into standard form. With multiplication and division we can work it out without writing numbers out in full - it's much quicker. Start by multiplying (or dividing) the first part of each number together (the number that is between 1 and 10). Then for the X10 part we make use of the indices rules. For multiplication we add the powers together and for division we subtract the powers. Much faster than writing the numbers out into ordinary numbers!! The one thing to be careful about with multiplication and division of numbers in standard form is that the final answer is actually in standard form - so the first number has to be between 1 and 10. When you multiply or divide it quite often will be too big or too small, so you need to rewrite this number into correct standard form - at this stage I always think it's easiest to write the number out into an ordinary number and then back into standard form to make sure you don't make a mistake.