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Comparing with z-scores

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People tend to be members in the Senate later in their careers than they are in the House of Representatives. Here are some summary statistics for the ages of members of the House of Representatives and the Senate one year in the United States.
GroupMean ageStandard deviation
Senateμ=62 yearsσ=10 years
House of Representativesμ=58 yearsσ=11 years
The Senate minority leader that year was 66 years old, while the House of Representatives minority leader was 76 years old.
Relative to their group, which leader was older?
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