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      <isProvisionFinancialSupport>false</isProvisionFinancialSupport>
      <isIPAReportInternalControl>true</isIPAReportInternalControl>
      <isChangeAccPrinciples>false</isChangeAccPrinciples>
      <isInfoRequiredEO>false</isInfoRequiredEO>
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    <signature registrantSignedName="MFS SERIES TRUST X" signedDate="2019-02-13" signature="Kasey Phillips" title="Assistant Treasurer"/>
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