**Quote:**

The math... step by step is 500,000 divided by 8 = 50 machines make 65,000 per hour.

500,000 / 8 = 62,500. If you do the rest of the calculations, you'll see that it'll lead you to the answer choice B, 10 hr.

**Quote:**

How can it take 400 hours to make 500k when it is stated in the problem that it takes 8 hours?

Here we deal NOT with 400 hours, but with 400 press-hours. It's often useful to deal with man-hours, car-hours, etc.

The value, 400 press-hours, tells us that it would take 1 press 400 hours to get the job done. If 400 presses do it, it will take them 1 hour. If 4 presses do it, it will take them 400/4 = 100 hours. And so on.