J=60, P=15
60 is 4 times as big as 15 (15 x 4 = 60).
When José gives away 50, he is left with 10 (60 - 50 = 10).
When Philippe gives away 5 cards, he is also left with 10 (15 - 5 = 10).
Therefore, both of them have the same amount of cards in the end.
