We have a urn with 25 balls, including 12 black balls and 13 white balls. We take 5 balls form urn with return.What is probability all 5 balls are black?

1 Answer
Feb 19, 2018

#0.0254803968#

Explanation:

If there are 25 balls and 12 are black and 13 are white, the probability of picking a black ball is:

#P("Black")=12/25#

Since we are replacing the ball each time there will always be 25 balls in total. The probability of picking another black ball is the same as the first.

Probability of all 5 events in succession is:

#P("Black")=12/25*12/25*12/25*12/25*12/25=(12/25)^5=0.0254803968#