Three helicopter crewmen are needed in an emergency. There are six crewmen on duty. In how many ways could three of them be chosen to fly the machine?
| A. | 20 |
| B. | 17 |
| C. | 30 |
| D. | 15 |
Answer : A Explanation : n = 6, r = 3 Combinations = n!/(r!(n - r)!) = 6!/(3!(6 - 3)!) = (6 x 5 x 4)/(3 x 2 x 1) = 20 Hence the answer is (a). |
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Option: A Explanation : Explanation will come here. Explanation will come here. Explanation will come here. Explanation will come here. Explanation will come here. |
