Standard form calculations
When you add, subtract, multiply and divide standard forms.
There are two methods
Method 1 - Actually calculate
Either turn the calculation so that you can add, subtract, multiply and divide and use a calculator.
Or
Method 2 - Use indices rules
Use the rules taught by Indices Mammoth memory to add or subtract the powers.
In fact, the best way is to use both and you have a method then to double-check you have the correct answer.