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                                                                     EXHIBIT 11


                    MAPCO INC. AND CONSOLIDATED SUBSIDIARIES
                STATEMENT RE: COMPUTATION OF PER SHARE EARNINGS
                    (In Millions, except per share amounts)

<TABLE>
<CAPTION>
                                                          Three Months             Six Months
                                                         Ended June 30,          Ended June 30,
                                                       -------------------    -------------------
                                                         1997       1996        1997       1996
                                                       --------   --------    --------   --------
<S>                                                    <C>        <C>             <C>    <C>     
PRIMARY EARNINGS PER COMMON SHARE
Computation for Consolidated Statements of Income
  Net income (loss)(a)                                 $   10.7   $  (21.0)       83.4   $   34.2
                                                       ========   ========    ========   ========
  Weighted average common shares outstanding               54.3       57.7        54.8       57.9
  Common stock equivalents (stock options)                                        --         --
                                                       --------   --------    --------   --------
  Weighted average common shares outstanding (a)           54.3       57.7        54.8       57.9
                                                       ========   ========    ========   ========
  Primary earnings (loss) per common share (a)(c)      $    .20   $   (.36)   $   1.52   $    .59
                                                       ========   ========    ========   ========

Additional Primary Computation
  Net income (loss) (a)                                $   10.7   $  (21.0)   $   83.4   $   34.2
                                                       ========   ========    ========   ========
  Weighted average common shares outstanding (a)           54.3       57.7        54.8       57.9
  Dilutive effect of outstanding options (d)                 .6       --            .7         .2
                                                       --------   --------    --------   --------
  Weighted average common shares outstanding,
    as adjusted                                            54.9       57.7        55.5       58.1
                                                       ========   ========    ========   ========
  Primary earnings (loss) per common share, as
    adjusted (b)                                       $    .20   $   (.36)   $   1.50   $    .59
                                                       ========   ========    ========   ========

FULLY DILUTED EARNINGS PER COMMON SHARE
Additional Fully Diluted Computation
  Net income (loss) (a)                                $   10.7   $  (21.0)   $   83.4   $   34.2
                                                       ========   ========    ========   ========
  Weighted average common shares outstanding (a)           54.3       57.7        54.8       57.9
  Dilutive effect of outstanding options (d)                 .6       --            .7         .3
                                                       --------   --------    --------   --------
  Weighted average common shares outstanding,
    as adjusted                                            54.9       57.7        55.5       58.2
                                                       ========   ========    ========   ========
  Fully diluted earnings (loss) per common share,
    as adjusted (b)                                    $    .20   $   (.36)   $   1.50   $    .59
                                                       ========   ========    ========   ========
</TABLE>


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                                   EXHIBIT 11


(a)     These figures agree with the related amounts in the condensed
        consolidated statements of income.

(b)     This calculation is submitted in accordance with Securities
        Exchange Act of 1934 Release No. 9083, although not required by
        footnote 2 to paragraph 14 of APB Opinion No. 15 because it results
        in dilution of less than 3%.

(c)     In 1997 and 1996, stock options are not included in the earnings per
        share computation included in MAPCO's condensed consolidated statements
        of income because the dilutive effect is less than 3%.

(d)     On September 10, 1996, the Board of Directors authorized a two-for-
        one stock split effected in the form of a stock dividend from
        shares held as treasury stock, which was distributed on September
        30, 1996, to shareholders of record on September 16, 1996.  All
        references in this Exhibit 11 to number of shares and per share
        amounts of the Company's common stock have been retroactively
        restated to reflect the increased number of shares outstanding.
        The dilutive impact of outstanding options was not considered for
        the three months ended June 30, 1996, because the loss for the
        quarter would make these calculations anti-dilutive.



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