Theodora Kracaw Kroeber Quinn (March 24, 1897 July 4, 1979) was a writer and anthropologist, best known for her accounts of Ishi, the last member of the Yahi tribe of California, and for her retelling of traditional narratives from several Native Californian cultures.

Based on that paragraph can we conclude that this sentence is true?
Ishi, the last member of the Yahi tribe, was 90 years old.
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