Sandy pays $120 for 4 violin lessons. How much does she pay for 8 violin lessons?

There were 816 people at a concert when a band started to play. after each song, only half the people stayed to hear the next song. how many people were left at the concert after x songs? write a function to represent this scenario.

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?

How do you find the circumfrance of a circle?