Question

Suppose a bag of marbles has 4 green, 2 red, 5 yellow, 1 brown, and 7 blue marbles. What is the probability of picking a blue marble, not replacing it, and picking a brown marble?

Answer 1

There are a total of 19 marbles. 

The chance of picking a blue marble is $\frac{7}{19}$

Since you didn't put that marble back in, there are 18 marbles still in the bag.

The chance of picking a brown marble is $\frac{1}{18}$

Multiplying the two values together results with $\frac{7}{342}$

Answer 2

The probability of picking a blue marble and not replacing it is 7 out of 19