In a bag of balls, 3 are red, 2 are blue and 5 are green. Two balls are selected from the bag. Calculate the probability that both are green.
Answer:2/9On the first pick of the bag, there are 10 balls in total. Out of these balls, 5 are green. Therefore the probability of picking a green ball will be 5/10 or 1/2. On the second pick of the bag, there are now 9 balls. Out of the 9 balls, 4 balls are green. Therefore, the probability of selecting a green ball on the second pick is equal to 4/9. As the first pick and second pick of the bag are independent events, the probability of picking two green balls is equal to 1/2 * 4/9. By multiplying the denominators together and the numerators together, the probability is found to be 4/18 or 2/9.
CH
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