scientific notation: 0.00039

How do I know which to use? Either 3.9*10^-4 or 0.39*10^-3

Question

scientific notation: 0.00039

How do I know which to use? Either 3.9*10^-4 or 0.39*10^-3

anonymous · Answer

When you move the decimal to the right its a negative when you move it to the left its a positive.

anonymous · Answer

the decimal point is place after the first digit folloed by x 10 to a power that is either negative or positive (the power shows how many decimal places you moved)

anonymous · Answer

The answer would then be 0.39*10^-3? But the both equal the same thing. -_-

anonymous · Answer

they both do equal the same thing but the decimal should be behind a number greater than 0

phi · Answer

the convention is you want a number between 1  and 9.99999

anonymous · Answer

i was just about to say that lol but thank you @phi , yes it has to be a single digit between 1 and 9.99999.

anonymous · Answer

So, it always have to be a single digit?

phi · Answer

the leading number (characteristic) is 1.0≤ x < 10.0

anonymous · Answer

yes