Number of cards = 52 (but on a picture are 48 cards)
Number of black cards = 26
Number of black and divisible by 5 cards = 4
[tex]5\spadesuit,\ 10\spadesuit,\ 5\clubsuit,\ 10\clubsuit[/tex]
[tex]\dfrac{4}{52}=\dfrac{1}{13}[/tex]
Answer: [tex]\boxed{\dfrac{1}{13}}[/tex]
