There are 3 white and 4 black balls in the urn. Two balls are taken out of the urn. Find the probability that both balls will be white.

Since there are 3 + 4 = 7 balls in the urn, the probability of pulling out the white first will be 3/7.
After we pull out the first ball (we are lucky and it will be white), then there will be 6 balls, which means that the probability of getting the white ball a second time will be:
2/6 = 1/3.
Since we are interested in both of these events, the answer is the product of the probabilities:
1/3 * 3/7 = 1/7 = 0.14
Answer: 0.14