Kinda need help. not fully understanding it

Ablock of wood is a cube whose side is x in. long. you cut off a 1-inch thick piece from the entire right side. then you cut off a 3-inch thick piece from the entire top of the remaining shape. the volume of the remaining block is 2,002 in3. what are the dimensions of the original block of wood?

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

Equation for the calculation double 2 and then add 5