Answer:
The mixture contains 47 lb of Colombian Supreme and 3 lb of Mocha Java.
Explanation:
We are given the following in the question:
Let x be the amount of Colombian supreme and y be the amount of Mocha java in the mixture.
Total amount of mixture = 50 lb
Thus, we can write the equation:

Total unit cost of mixture = $5.93/lb
Cost of Colombian Supreme = $4.99/lb
Cost of Mocha Java = $5.99/lb
Thus, we can write the equation:

Solving the two equations by elimination method,

Thus, the mixture contains 47 lb of Colombian Supreme and 3 lb of Mocha Java.