<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><Version>2.2.0.25</Version><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><ReportLongName>006030 - Disclosure - Inventories</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelColumn>false</LabelColumn><CurrencyCode>USD</CurrencyCode><FootnoteIndexer /><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><MCU><KeyName>9/1/2010 - 2/28/2011
USD ($)

USD ($) / shares
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MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;(3) Inventories are valued on a lower of last-in, first-out (LIFO) cost or market basis.&amp;#160;&amp;#160;At February 28, 2011, August 31, 2010 and February 28, 2010, inventories would have been greater by $1,477 million, $1,379 million and $1,301 million respectively, if they had been valued on a lower of first-in, first-out (FIFO) cost or market basis.&amp;#160;&amp;#160;LIFO inventory costs can only be determined annually when inflation rates and inventory levels are finalized; therefore, LIFO inventory costs for interim financial statements are estimated. Inventory includes product costs, inbound freight, warehousing costs and vendor allowances not included as a reduction of advertising expense.&lt;/font&gt;&lt;/div&gt;</NonNumbericText><NonNumericTextHeader>(3) Inventories are valued on a lower of last-in, first-out (LIFO) cost or market basis.&amp;#160;&amp;#160;At February 28, 2011, August 31, 2010 and February 28,</NonNumericTextHeader><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios></Cell></Cells><OriginalInstanceReportColumns /><Unit>Other</Unit><ElementDataType>us-types:textBlockItemType</ElementDataType><SimpleDataType>string</SimpleDataType><ElementDefenition>This element represents the complete disclosure related to inventory. This may include, but is not limited to, the basis of stating inventory, the method of determining inventory cost, the major classes of inventory, and the nature of the cost elements included in inventory. If inventory is stated above cost, accrued net losses on firm purchase commitments for inventory and losses resulting from valuing inventory at the lower-of-cost-or-market may also be included. For LIFO inventory, may disclose the amount and basis for determining the excess of replacement or current cost over stated LIFO value and the effects of a LIFO quantities liquidation that impacts net income.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher AICPA
 -Name Accounting Research Bulletin (ARB)
 -Number 43
 -Chapter 3
 -Section A
 -Paragraph 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 02
 -Paragraph 6
 -Subparagraph a, b, c
 -Article 5

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