some exersise books have to be arranged in piles with 10 or 15 or 20 books per pile . what is the least number of books needed to do this?

Sara needs to take a taxi to get to the movies the taxi charges $4.00 for the first mile and then $2.75 for each mile after that if the total charge is $20.50 then how far was sara’s taxi ride to the movie

Translate this phrase into an algebraic expression. 21 more than twice goran's savings use the variable g to represent goran's savings. need to know fast.

How do i do this? i don’t understand