SOLUTION: A bag contains 7 white 5 black and 4 red balls. If 2 balls are drawn at random. What is probability of selecting 1.both the balls are white 2.one is black and other is red

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Question 1109135: A bag contains 7 white 5 black and 4 red balls. If 2 balls are drawn at random.
What is probability of selecting
1.both the balls are white
2.one is black and other is red
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1. Without replacement,
P%28WW%29=+%287%2F16%29%286%2F15%29+=7%2F40
With replacement,
P%28WW%29=%287%2F16%29%287%2F16%29=49%2F256
.
.
2. Without replacement,
P=P%28WR%29%2BP%28RW%29=+%287%2F16%29%284%2F15%29%2B%284%2F16%29%287%2F15%29+=7%2F30
With replacement,
P=P%28WR%29%2BP%28RW%29=+%287%2F16%29%284%2F16%29%2B%284%2F16%29%287%2F16%29+=7%2F32