MHT CET202122 Sep 2021Evening ShiftMathematicsDefinite IntegrationActual
A fair coin is tossed 4 times. If X a random variable which indicates number of heads, then P [ X < 3]=
Options
- A10 16
- B1 16
- C12 16
- D11 16
Correct answer
D. 11 16
Step-by-step solution
A coin is tossed 4 times n ( S )=2^4=16 Following possibilities exist. (i) All Heads 1 way (ii) 3 Heads, 1 Tail 4 ! 3 ! =4 ways (iii) 2 Heads, 2 Tails 4 ! 2 ! 2 ! =6 ways (iv) 1 Head, 3 Tails 4 ! 3 ! =4 ways (v) 0 head, 4 Tails 1 way Required probability. aligned & = P ( x =0,1,2)= 1 16 + 4 16 + 6 16 & = 11 16 aligned