One bag contain 3 blue and 5 red balls, another bag contain 2 blue and 4 red balls respectively. One ball is drawn for each bag. What is the probability both balls are blue
A. \( \frac{2}{15} \) B. \( \frac{3}{24} \) C. \( \frac{3}{21} \) D. \( \frac{3}{28} \)
Correct Answer: D
Explanation
One bag with 3 blue and 5 red Pr (H) = 3/8Pr (r) 5/8 Another bag with 2 blue and 4 red (note one ball is drawn from each bag) i.e. prob.=8 − 1 = 7 prob. (2 ball both are blue=pr (1st blue and 2nd blue) prob. 2 balls both blue = 3/8 × 2/7 = \( \frac{3}{28} \)
