SOLUTION: Given that log8 5 = 0.7740 and log8 11 = 1.1531 evaluate the expression log8 320

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Question 1029068: Given that
log8 5 = 0.7740
and
log8 11 = 1.1531
evaluate the expression
log8 320
Found 2 solutions by Boreal, ikleyn:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
log 8 (320)=log 8 (5)+log 8(64)=2.7740, because log 8 (64)=2.
Check with change of base formula
log8 320=log 10 320/log 10 8= 2.77397

Answer by ikleyn(52794) About Me  (Show Source):
You can put this solution on YOUR website!
.
Given that
log8 5 = 0.7740
and
log8 11 = 1.1531
evaluate the expression
log8 320
~~~~~~~~~~~~~~~~~~~~~~~~~~~ 

320 = 5*64 = 5%2A8%5E2

Therefore,  log%288%2C+%28320%29%29 = log%288%2C+%285%2A8%5E2%29%29%29 = log%288%2C%285%29%29+%2B+2 = 0.7740 + 2 = 2.7740.

The info on log%288%2C%2811%29%29 is excessive and is not used in this evaluation.