How do you write #6(2.2 xx 10^10)# in standard notation?
I can think of 2 ways to explain this. I'll explain a second one after I explain this one.
Use your favorite multiplication method to get
This answer is the correct number, but it is in neither standard notation nor scientific notation. We should choose one notation or the other. We'll use scientific notation.
On re-reading, I see that you did ask how to write this in standard notation:
Using the usual rules for significant figures the answer should be
(Like many mathematicians, I tend to carry more significatn figures than I have a right to.)
If you chose to (if it is clearer to you) You could re-write both numbers in scientific notation to start with:
Again keeping the correct significant figures: