Given:
Event A : the card has the number 8
Event B : the card is blue
The probability of each events are given as:
P (A) = 1/10
P (B) = 1/4
P(A and B) = 1/10 x 1/4 = 1/40
From thea above information, we can see that the outcome of the event A cannot affect the outcome of the event B.
Therefore, the two events are independent.