The answer is:  " x = 105.41 " . 
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Explanation:
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Given:   " 24 log (3x) = 60 " ;  Solve for "x" .
The default is to assume "base 10" for the "logarithm". 
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Start by dividing each side of the equation by "24" ; 
        →   [ 24 log(3x) ] / 24  = 60 / 24 ; 
to get:  
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  log (3x)  = 2.5 ;
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Rewrite as:  log₁₀ (3x) = 2.5 ;  
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Using the property of logarithms:
⇔    10⁽²·⁵⁾  =   3x  ;  
↔   3x = 10⁽²·⁵⁾   ; 
          →  10^ (2.5) = 316.2277660168379332 ; 
      →  3x = 316.227766016837933 ;  
Divide each side of the equation by "3" ; 
   to isolate "x" on one side of the equation; 
       and to solve for "x" ; 
     →  3x / 3 =  316.2277660168379332 / 3  ; 
to get: 
     →   x = 105.4092553389459777333 ; 
     →  round to 2 (two) decimal places; 
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          →   " x = 105.41 " .
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  Hope this helps!
     Best wishes to you!
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