SOLUTION: Given that log[a]5=0.8271 and log[a]20=1.5395 fing log[a]4

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Question 206004: Given that log[a]5=0.8271 and log[a]20=1.5395 fing log[a]4
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Given that log[a]5=0.8271 and log[a]20=1.5395 fing log[a]4

Use the two facts:

1. 4+=+20%2F5

2. log%28X%2C%28Y%2FZ%29%29=log%28X%2C%28Y%29%29-log%28X%2C%28Z%29%29

log%28a%2C%284%29%29 

Replace %284%29 by %2820%2F5%29

log%28a%2C%2820%2F5%29%29

Use 2 above with X=a, Y=20, Z=5

log%28a%2C%2820%2F5%29%29=log%28a%2C%2820%29%29-log%28a%2C%285%29%29=1.5395-0.8271=0.7124 

Edwin