Question: I need help with this problem:
Some people got on a bus at the terminal. At the first bus stop, 5 more people got in. Then at the second bus stop, 7 people got down and 8 more got in. If there were a total of 20 people heading to the third stop, how many people got on the bus at the terminal?
Answer: 
There were 20 - 8 = 12 people on the bus before 8 people got in at the second stop.
There were a total of 12 + 7 =19 people at the second stop before 7 people went down.
So, 19 - 5 = 14 people got on the bus at the terminal.