SOLUTION: Evaluate the expression by using logarithms. Round answer to the nearest tenth: {{{(37.9*sqrt(488))/(1.28)^3}}}

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Question 877693: Evaluate the expression by using logarithms. Round answer to the nearest tenth:
%2837.9%2Asqrt%28488%29%29%2F%281.28%29%5E3
Found 2 solutions by Alan3354, cigany29:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
--> log(37.9) + 0.5*log(488) - 3log(1.28)
=~ 771.1
----------------
Calculators use logs internally.

Answer by cigany29(23) About Me  (Show Source):
You can put this solution on YOUR website!

let A = %28%2837.9%2A+sqrt%28488%29%29%2F1.28%5E3%29
log A=log%28%2837.9%2Asqrt%28488%29%29%2F1.28%5E3%29
=log%2837.9%29+%2B+%281%2F2%29%2Alog%28488%29+-+3log%281.28%29
=1.5786 +(1/2)*2.6884 - 3*0.1072
=1.5786 + 1.3442 - 0.3216
=2.6012
A=antilog2.6012
A=10^(2.6012)
A=399.2
Check it:
%2837.9%2Asqrt%28488%29%29%2F%281.28%29%5E3
=837.2384%2F2.0972
=399.2
and that's how to get'er done!