I pretty sure the answer to the first question is 3,000. I got this by adding the 272 more Carter got to the 764 and then adding the 764 that Jack collected. I then got 1,800. I divided it by 3 cause it was 3/5 of the final project. I got 600 from that. The I did 600 times 5 and got 3,000. I don't know if it's right but it might help...
6/2000 = x / 25,000.....6 lbs to 2000 sq ft = x lbs to 25,000 sq ft cross multiply (2000)(x) = (6)(25,000) 2000x = 150,000 x = 150,000/2000 x = 75 <== 75 lbs
