It takes a plane 3.5 hours to fly 2345 miles and 2 hours to fly 860 miles going the opposite direction. In determining mph for each leg, what system of equations might be helpful?

The dolphins at the webster are fed 1/2 of a bucket of fish each day the sea otters are fed 1/2 as much fish as the dolphins how many buckets of fish are the sea fed each day? simplify you answer and write it as a proper fraction or as a whole or mixed number