Question 197791
AT LEAST YOU GAVE IT A TRY!!!!!

Let's check your answer:

The diesel travelled 11 hours at 22 mph or 242 mi; the freight train travelled 1 hour at 20 mph or 20 mi; 242 + 20 does not add up to 680 Mi

If you laid out these word problems so we know what x stands for, it would 
usually make the problem easier

Distance(d) equals Rate(r) times Time(t) or d=rt; r=d/t and t=d/r
Let r=rate of the diesel train
Total distance diesel train travelled=r*10 or 10r+r*1=11r

Total distance freight train travelled =20*1=20 mi

Ande we are told that the above two distances add up to 680 mi, so:
11r+20=680 subtract 20 from both sides
11r=660 divide each side by 11
r=60 mph-------------------rate of the diesel


Hope this helps---ptaylor