## mathmath333 one year ago Probability question

1. mathmath333

\large \color{black}{\begin{align} & \normalsize \text{10 black and 5 white balls. Two balls are drawn from the}\hspace{.33em}\\~\\ & \normalsize \text{urn one after the other without replacement. What is the}\hspace{.33em}\\~\\ & \normalsize \text{ probability that both drawn balls are black? }\hspace{.33em}\\~\\ \end{align}}

2. misty1212

HI!!

3. misty1212

what is the probability that the first one is black?

4. mathmath333

robability that the first one is black=2/3

5. mathmath333

hii!

6. misty1212

ok now how many black balls are left in the urn?

7. mathmath333

9

8. misty1212

right and how many balls total?

9. mathmath333

14

10. misty1212

so therefore the probability that the second ball chosen is black, given that the first ball was black, is ?

11. mathmath333

9/14

12. misty1212

exactly

13. misty1212

your final job is $\frac{2}{3}\times \frac{9}{14}$

14. mathmath333

3/7

15. misty1212

ok looks good