If you borrow $50 from your mom and $50 from your dad it makes $100. so the shirt you buy is $97. then you have $3 left. so you keep $1 and you give $1 to your mom and $1 to your dad. so now u owe them $49 each. $49 plus $49 is $98 plus then $1 you have it is $99. so where is the other $1.

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