Statistics
posted by Laura
A bucket has 3 blacks and 7 red balls.
(a) What is the probability of drawing a black fall on the first draw? (my answer  3/10 x 100 = 30%) (b) What is the probability of drawing a red ball on the 2nd draw if you replace the black ball you drew on the first draw? (my answer  7/10 x 100 = 70%) (c) How would your answer to (b) change if you don't replace the ball you drew? (my answer 7/9 x 100 = 77.78%) (d) What is the probability of drawing a red, red and black in that order? (assume replacement after each draw) (my answer 7/10 x 7/10 x 3/10 = .0147) Please verify. Thank you

PsyDAG
Verified! Good work!
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