MHT CET202121 Sep 2021Evening ShiftMathematicsThree Dimensional GeometryActual
An urn contains 9 balls of which 3 are red, 4 are blue and 2 are green. Three balls are drawn at random from the urn. The probability that the three balls have difference colours is
Options
- A1 14
- B3 14
- C1 7
- D2 7
Correct answer
D. 2 7
Step-by-step solution
aligned Required probability & = ^3 C ₁ ^4 C ₁ ^2 C ₁ ^9 C ₃ & = 3 4 2 ( 9 ! 3 ! 6 ! ) = 24 6 9 8 7 = 2 7 aligned