A. 20.5 lb copper and 4.5 lb tin
A given alloy contains 20% copper and 5% tin. How many pounds of copper and of tin must be melted with 100 lb of the given alloy to produce another alloy analyzing 30% copper and 10% tin? All percentages are by weight.
B. 17.5 lb copper and 7.5 lb tin
C. 19.5 lb copper and 5.5 lb tin
D. 18.5 lb copper and 6.5 lb tin