The answer is 79.9 g.
Copper takes 92.0% of aluminum bronze and it is a limiting factor. We have aluminum in excess, so we need to make a proportion.
If 73.5 g of copper are 92.0%, how many g of aluminum bronze will be 100%:
73.5 g : 92.0% = x : 100%.
x = 73.5 g : 100% * 92.0%
x = 79.9 g
Therefore, from 73.5 g of copper and 6.4 g of aluminum (since 79.9 g - 73.5 g = 6.4 g), maximum 79.9 g of aluminum bronze can be prepared.
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