Instructions:
For problems 1-2, find the solution if possible. If there is not enough information to solve the problem or if it as no solution, say so.

1. At noon a train leaves Bridgton heading east at 90 mi/h to Cogsville, 450 mi away. At 12:15 pm a train leaves Cogsville heading west to Bridgton at 100 mi/h. At what time will they pass each other?
The answer is 2:30 pm I just want to know how to get it. D:
2. In a bicycle race, Lion gives Robert a 500 m advantage. Also, Lionel agrees to start 15 min after Robert. If Lionel bikes at 17 km/h and Robert at 14 km/h, how long will it take Lionel after he starts biking to overtake Robert?

And:
In this exercise, choose a variable to represent an unknown number, and then write an equation to describe the given situation(don't need the answer just the equation):

Tom and Tina set out on their bikes at noon and travel toward each other, meeting at 2:30 p.m. Tina's speed is 4 mi/h faster than Tom's speed, and their starting points are 50 mi apart.

Thanks in advance.