(1) let "r" denote number of rabbits, "c" number of chickens
Set up the equations:

Answer: There are 575 rabbits and 425 chickens
(2) m - number of Mike's stamps, a - number of Andrew's stamps.
Set up equations:

Answer: Mike has 48 stamps. Andrew has 12 stamps.
I equals 70 grams cup because
If you were to draw the cosx and sinx graph there will be infinite solutions at their interceptions which are the multiple of pi/4