Train A starts at 4 miles South of a bridge and heads North at a constant speed of 30 miles per hour. Train B starts 6 miles North of the bridge.

a.

What velocity must Train B have so that the two trains cross the bridge at the same time?

b.

If Train B goes at 35 miles per hour, South, how far away from the bridge do they cross?

• Hints
• Solution: part a.
• Solution: part b.