This algebraic systems of equations word problem has got me stuck.?

Question

A plant food is to be made from three chemicals. The mix must include 60% of the first and second chemicals. The second and third chemicals must be in a ratio of 4 to 3 by weight. How much of each chemical is needed to make 750 kg of the plant food?

The damn ratio in this word problem has me clueless. The book doesn't teach them for another 3 chapters. Help on this word problem would be appreciated.

Answer 1

Please refer back to your previous question, where I have just completed the solution (except for the very last step). You shouldn't have any trouble with that now.