Many seemingly impossible feats were carried out during the building of the railroads. Imagine a crew of workers building 10 miles of track in a day. Workers of the Central Pacific Railroad did just that, setting a record that still stands.

Imagine the enormous amounts of supplies necessary to complete a railroad. The following problems are based on numbers from this amazing feat. Show your work as you solve these problems.

1. How long will it take a crew to build 25 miles of track if that crew can build 10 miles in 12 hours?
   
   
2. If a track has 3,520 rails and 25,800 ties, how many ties are spiked to each rail?
   
   
3. There are 450 railroad workers. Each worker lifts 250,000 pounds of materials. How many pounds were lifted all together?
   
   
4. If a crew begins work at 7 a.m. and lays 6 miles of track by 1:30, how long did it take to lay those 6 miles?
   
   At that same rate, how many miles of track will the crew lay by 8 p.m.? At what time will 18 miles of track be completed?
   
   
5. A crew lays 25,800 ties in 12 hours. What is the average number of ties laid per hour? If 450 workers laid those ties, what is the average number of ties laid per worker per hour?