Andrew has six fewer coins than Casey. Bob has two more than twice as many coins as Andrew. Altogether, they have 504 coins. How many coins does Bob have?

Relax

Respuesta :

Andrew: x - 6
      Bob: 2x - 12
  Casey: x

  (x - 6) + (2x - 12) + x = 504
(x + 2x + x) + (-6 - 12) = 504
                        4x - 18 = 504
                            + 18   + 18
                               4x = 522
                                4       4
                                 x = 130.5