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Exhibit 12.2

Marathon Oil Corporation
Computation of Ratio of Earnings to Fixed Charges
TOTAL ENTERPRISE BASIS—Unaudited
(Dollars in Millions)

	Year Ended December 31
	2004		2003		2002		2001		2000
Portion of rentals representing interest	$	57	$	63	$	66	$	54	$	50
Capitalized interest, including discontinued operations		48		41		16		27		19
Other interest and fixed charges, including discontinued operations		279		270		316		349		375
Total fixed charges (A)	$	384	$	374	$	398	$	430	$	444
Earnings-pretax income with applicable adjustments (B)	$	2,843	$	2,422	$	1,446	$	3,365	$	1,884
Ratio of (B) to (A)		7.40		6.48		3.63		7.83		4.24

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Exhibit 12.2

Marathon Oil Corporation Computation of Ratio of Earnings to Fixed Charges TOTAL ENTERPRISE BASIS—Unaudited (Dollars in Millions)