Atotal of 17,100 seats are still available for the next hockey game. if 62% of the tickets are sold, how many seats are in the arena?

Pls! does anybody know a shortcut for answering these types of questions in the future?

Miguel’s teacher asks him to color 4/8 of his grid. he must use 3 colors: red, blue, and green. there must be more green sections than red sections. how can miguel color all the sections of his grid to follow all the rules

2.5 milligrams is equivalent to how many grams