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                                                                    EXHIBIT 11.1
 
                             METAL MANAGEMENT, INC.
 
                   COMPUTATION OF NET INCOME (LOSS) PER SHARE
                    (IN THOUSANDS, EXCEPT PER SHARE AMOUNTS)
 
<TABLE>
<CAPTION>
                                                THREE MONTHS   THREE MONTHS   NINE MONTHS    NINE MONTHS
                                                   ENDED          ENDED          ENDED          ENDED
                                                DECEMBER 31,   DECEMBER 31,   DECEMBER 31,   DECEMBER 31,
                                                    1998           1997           1998           1997
                                                ------------   ------------   ------------   ------------
<S>                                             <C>            <C>            <C>            <C>
Earnings:
  Net loss from continuing operations
     applicable to Common Stock...............    $(19,043)      $(36,334)      $(38,172)      $(36,191)
  Gain (loss) on sale of discontinued
     operations, net..........................          21            (42)            95            166
  Extraordinary charge, net...................         (76)             0           (938)             0
                                                  --------       --------       --------       --------
     Net loss applicable to Common Stock......    $(19,098)      $(36,376)      $(39,015)      $(36,025)
                                                  ========       ========       ========       ========
Basic earnings per share:
  Weighted average common shares
     outstanding..............................      41,381         21,699         37,506         17,067
                                                  ========       ========       ========       ========
Per share amounts:
  Net loss from continuing operations
     applicable to Common Stock...............    $  (0.46)      $  (1.67)      $  (1.02)      $  (2.12)
  Gain (loss) on sale of discontinued
     operations...............................    $   0.00       $  (0.01)      $  (0.00)      $   0.01
  Extraordinary charge, net...................    $   0.00       $   0.00       $  (0.02)      $   0.00
                                                  --------       --------       --------       --------
     Net loss applicable to Common Stock......    $  (0.46)      $  (1.68)      $  (1.04)      $  (2.11)
                                                  ========       ========       ========       ========
Diluted earnings per share:
  Weighted average common shares
     outstanding..............................      41,381         21,699         37,506         17,067
  Common stock equivalents(1).................           0              0              0              0
                                                  --------       --------       --------       --------
     Total....................................      41,381         21,699         37,506         17,067
                                                  ========       ========       ========       ========
Per share amounts:
  Net loss from continuing operations
     applicable to Common Stock...............    $  (0.46)      $  (1.67)      $  (1.02)      $  (2.12)
  Gain (loss) on sale of discontinued
     operations...............................    $   0.00       $  (0.01)      $  (0.00)      $   0.01
  Extraordinary charge, net...................    $   0.00       $   0.00       $  (0.02)      $   0.00
                                                  --------       --------       --------       --------
     Net loss applicable to Common Stock......    $  (0.46)      $  (1.68)      $  (1.04)      $  (2.11)
                                                  ========       ========       ========       ========
</TABLE>
 
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(1) For all periods presented, common stock equivalents were not added to the
    weighted average shares outstanding as the result would have been
    anti-dilutive.
 
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