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Natalya put 14 blue marbles, 14 red marbles, and no other marbles into 3 empty cups. She put 2 blue marbles and 6 red marbles in Cup A, 6 blue marbles and 4 red marbles in Cup B, and 6 blue marbles and 4 red marbles in Cup C.
After this, Dmitry will randomly pick three marbles, one from each cup. Consistent with the given information, select for 3 blue the probability that Dmitry will pick 3 blue marbles, and select for 3 red the probability that Dmitry will pick 3 red marbles. Make only two selections, one in each column.
0.090
0.120
0.125
0.150
0.250
0.500
Let's visualize this problem to make it crystal clear.
Let's create a simple table to organize our marble distribution:
| Cup | Blue Marbles | Red Marbles | Total |
| A | 2 | 6 | 8 |
| B | 6 | 4 | 10 |
| C | 6 | 4 | 10 |
| Total | 14 | 14 | 28 |
We can verify our totals: \(2+6+6 = 14\) blue ✓ and \(6+4+4 = 14\) red ✓
Dmitry will randomly pick exactly one marble from each cup. We need to find:
Since he picks one marble from each cup independently, we'll multiply the individual probabilities.
For Dmitry to pick 3 blue marbles, he needs:
Combined probability:
\(\mathrm{P(3\,blue)} = \frac{1}{4} \times \frac{3}{5} \times \frac{3}{5} = \frac{9}{100} = 0.090\)
For Dmitry to pick 3 red marbles, he needs:
Combined probability:
\(\mathrm{P(3\,red)} = \frac{3}{4} \times \frac{2}{5} \times \frac{2}{5} = \frac{12}{100} = 0.120\)
Based on our calculations:
These values match the answer choices provided, confirming our analysis.