SOLUTION: IF 5X10n=0.0005THENn=?

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Question 21828: IF 5X10n=0.0005THENn=?
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Let's start with 0.0005, and express this in scientific notation. If you already know how to do this, you can probably go straight to the answer. However, for those who do NOT know scientific notation, here is a refresher for you. Start with 0.5:

0.5+=+5%2F10 or 5%2A10%5E-1
0.05+=+5%2F100 or 5%2A10%5E-2
0.005+=+5%2F1000 or 5%2A10%5E-3
0.0005+=+5%2F10000 or 5%2A10%5E-4
0.00005+=+5%2F100000 or 5%2A10%5E-5
Of course, your answer to the problem that you posted is the exponent. So your final answer is n= -5.

Of course, once you understand this, you don't have to go through all of this. You just count the number of places you would have to move the decimal to have one digit to the left of the decimal, and since it is a very small decimal number, it is a negative power of 10.

No Extra Charge:
0.00000005+=+5%2A10%5E-8 (if I counted the zeros right!)

R^2 at SCC