Answer:
A: 14/65
Step-by-step explanation:
Let A be the event of pulling a blue marble first, there are 28 blue marbles
Let B be the event of pulling a red marble second, there are 12 red marbles
There are 40 total marbles in the bag.
So
P(A) = 28/40
Since he pulls two marbles with out replacement, there is one less marble in the bag when he pulls the second marble, so there are only 39 marbles left, so
P(B) = 12/39
When calculating the probability of multiple events, you multiply their probabilities together, so we have
P(A then B) = (28/40)(12/39) = 336/1560
Now reduce the fraction...
112/520
28/130
14/65
