Question

Jenna has a bag that contains 7 red marbles and 25 blue marbles. She selects a marble at random, and then, without replacing the first one, selects another marble at random.

What is the probability that Jenna selects a blue marble and then a red marble? Round your answer to the nearest percent.



P(blue and red) ≈

Answer 1

So if we have a total of 32 marbles in the bag and the first pull we want a blue we can say the total number of favorable outcomes is 25/32 then to pull a red marble is 7/31 because one marble had been removed.

25/32 x 7/31 = 0.176 So now we need to round to the nearest percent which would be 18% chance.

Answer 2

Jenna has a bag that contains the following
=> 7 red marbles
=> 25 blue marbles.
She selects a marble at random, and then, without replacing the first one, selects another marble at random.
=> 7 + 25 = 32 marbles are there in all.
For blue marble
=> 1/32 is the probability
For red
=> 1/31 is the probability
or
3%