SOLUTION: how to find log of 1.8*10^-7

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Question 571608: how to find log of 1.8*10^-7
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+log%28+1.8%2A10%5E%28-7%29+%29+
Use the rule:
+log%28+a%2Ab+%29+=+log%28a%29+%2B+log%28b%29+
--------------------------
+log%28+1.8+%29+%2B+log%28+10%5E%28-7%29+%29+
Use the rule:
+log%28+a%5Eb+%29+=+b%2Alog%28a%29+
---------------------
+log%28+1.8+%29+%2B+%28-7%29%2Alog%2810%29+
+.25527+-+7%2A1+
+-6.7447+
check answer:
On my Casio calculator,
+10%5E%28-6.7447%29+=+1.800114%2A10%5E%28-7%29+
I assume error is due to rounding off