Any one know this it’s exponential growth and decay

Richard save $32 in march he saved $48 in april and $38 in may then richard spent $113 on a keyboard how much money does richard have left

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).

Peyton's field hockey team wins 4 games out of every 7 games played. her team lost 9 games. how many games did peyton's team play?