SOLUTION: A box contains 7 red balls and 3 black balls. Two balls are drawn. What is the probability of drawing: (a)a red ball, followed by a black ball, assuming that you replace the fir

Question 667908: A box contains 7 red balls and 3 black balls. Two balls are drawn. What is the probability of drawing:
(a)a red ball, followed by a black ball, assuming that you replace the first ball before drawing the second?
(b)a black ball on each draw, if the first ball drawn is black (assuming there is no replacement)
Found 2 solutions by ewatrrr, act417:
Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!

Hi,
A box contains balls: 7 red balls and 3 black balls.
Two balls are drawn.
with replacement
P(red than black) =
without replacement
P(black than black) =
Answer by act417(1) (Show Source): You can put this solution on YOUR website!
I have no idea
RELATED QUESTIONS
A box contains 2 white balls, 3 black balls and 4 red balls. What is the probability of... (answered by Alan3354)
A box contains 6 white balls, 7 black balls, and 5 red balls. How many red balls must be... (answered by macston)
A box contains 20 balls out which 7 are white balls, 5 are black balls, 6 are red balls... (answered by Boreal)
A box contains 4 white balls and 3 red balls. Three balls are drawn from the box without (answered by Boreal)
a box contains 8 white balls, 4 black balls, and 9 red balls. how many red balls must be (answered by stanbon)
A box contains 20 balls out which 7 are white balls, 5 are black balls, 6 are red balls (answered by Edwin McCravy,ikleyn)
Urn 1 contains 6 red balls and 5 black balls. Urn 2 contains 3 red balls and 3 black... (answered by Boreal)
a box contains 7 identical red balls, 4 identical white balls and 9 identical black... (answered by stanbon)
Three boxes containing red, white and blue balls are used in an experiment. Box 1... (answered by CPhill)