The Sahas were reading a best-selling novel as a family. After the first week, they checked in with each other to see how much of the book each had read.

Don't know how to find x given these segment lengths

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

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class