Let probability of hitting target by P is E1 ,Q is E2 ,and by R is E3
From the question Required probability is P(E1)P(E2)P(E3ˉ)+P(E1ˉ)P(E2)P(E3ˉ)+P(E1)P(E2ˉ)P(E3ˉ)=(43)(21)(83)+(41)(21)(83)+(43)(21)(83)
=6412+9
=6421
Three persons P, Q and R independently try to hit a target. If the probabilities of their hitting the target are 43,21 and 85 respectively, then the probability that the target is hit by P or Q but not by R is:
Held on 8 Apr 2017 · Verified 6 Jul 2026.
6439
6421
649
6415
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