How many Donner Party members had died before the Great Salt Lake?

The total of deaths was thus 42, with 47 survivors

Explanation:

Five of the emigrants died before reaching the mountain camps, 34 at the camps or on the mountains while attempting to cross, and one just after reaching the settlements. Two men who had joined the party at the lake also died.  

Source: https://www.britannica.com/topic/Donner-party

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