Final answer:
The ratio of copper to zinc in an alloy is 4:5. The ratio of copper to the total alloy weight is 4:9, and the ratio of zinc to the total weight is 5:9.
Step-by-step explanation:
The question asks for the ratio of copper to zinc and their ratios to the total weight in an alloy. To find these ratios, we consider the weights of copper and zinc provided. With 120g of copper and 150g of zinc, the ratio of copper to zinc is 120g to 150g, which simplifies to a ratio of 4:5.
To calculate the ratio of copper to the total weight of the alloy, the total weight must first be determined by adding the mass of copper and zinc together: 120g + 150g = 270g. The ratio of copper to the total weight is then 120g:270g, which simplifies to 4:9. Similarly, the ratio of zinc to the total alloy weight is 150g:270g, simplifying to 5:9.
The calculations make sense because when you add the ratios of copper and zinc to the total weight, you get 4:9 + 5:9, which simplifies to 9:9, confirming that the two parts add up to the whole 100% of the alloy's weight.