HELP ASAP WILL MARK BRAINLIEST

Olivia uses the work below to determine 55% of 720 which explains the error in olivia’s solution

1foot = 12 inches; 1 yard = 3 feet

Expresa commuter train leaves downtown sation and travels at a average speed of 55 miles per hour towards the north side sation, which is 50miles away. thirty minutes later, express commuter train #7 leaves north side and travels at a average speed of 35miles per hour towards downtown sation. at the moment the two trains pass each other, how far(in miles) is train #12 from the downtown sation and how long(in minutes) has the #12 train been traveling