A machine puts golf balls into boxes and then loads the boxes into cases. The machine is normally able to load 25 cases of golf balls per hour. There are 20 boxes in one case. There are 12 balls in one box. Today, the machine is running a little faster than usual so that it takes 0.2 seconds less time to load one golf ball into a box than it normally does. What is the machine's new rate in cases of golf balls per hour?

Given that in 1 hour machine can load 25 cases of golf balls.

1 case of golf ball contains 20 boxes.

∴ 25 cases of golf ball contains = 25 × 20 boxes = 500 boxes.

1 box contains 12 golf balls

∴500 boxes contains = 500 × 12 golf balls = 6000 golf balls.

Hence we infer that 25 cases of golf balls contains 6000 golf balls.

We already have mentioned that machine can load 25 cases of golf ball in 1 hour.

i.e 6000 golf balls can be loaded in 1 hour (3600 seconds)

∴ 1 golf ball can be loaded in  = $\frac{3600}{6000} = 0.6 seconds$