If the probability of hitting a target by a shooter, in any shot, is [1 3], then the minim…

Question

If the probability of hitting a target by a shooter, in any shot, is $${1 \over 3}$$, then the minimum number of independent
shots at the target required by him so that the probability of hitting the target atleast once is greater than $${5 \over 6}$$ is :

Accepted Answer

$$1 - {}^n{C_0}{\left( {{1 \over 3}} \right)^0}{\left( {{2 \over 3}} \right)^n} > {5 \over 6}$$

$${1 \over 6} > {\left( {{2 \over 3}} \right)^n}\,\, \Rightarrow \,\,0.1666 > {\left( {{2 \over 3}} \right)^n}$$

$${n_{\min }} = 5$$

Solutions · 1