Question

Mike bought 4 new baseball trading cards to add to his collection. the next day his dog ate half of his collection. there are now only 42 cards left. how many cards did mike start with

Answer 1

(4 + x) / 2 = 42
(2) (2)

4 + x = 84
-4 -4

x = 80

Mike started with 80 cards

Hope I helped :)