A) 5
B) 6
C) 7
D) None of the above
Correct Answer: A
Solution :
[a] Probability of hitting the target = 0.3 If ?n? is the no. of times that the missile is fired. \[\therefore \] Probability of hitting at least once \[=1-{{[1-0.3]}^{n}}=0.8\] \[{{0.7}^{n}}=0.2\] \[n\log 0.7=\log 0.2\] \[\Rightarrow n=4.512\] for \[n=4;\,\,p<0.8\] take n = 5 \[\] Hence 5 missiles should be fired so that there is at least 80% prob. That the target is hit.You need to login to perform this action.
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