A) \[\frac{5}{{{2}^{10}}}\]
B) \[\frac{63}{{{2}^{9}}}\]
C) \[\frac{^{10}{{C}_{5}}}{{{2}^{10}}}\]
D) None of these
Correct Answer: B
Solution :
[b] The probability of hitting the target 5th time at the 10th throw = P (the probability of hitting the target 4 times in the first 9 throws) \[\times \] (the probability of hitting the target at the 10th throw) \[=\left[ ^{9}{{C}_{4}}{{\left( \frac{1}{2} \right)}^{4}}{{\left( \frac{1}{2} \right)}^{5}} \right]\left( \frac{1}{2} \right)=\frac{9!}{4!5!}\times {{\left( \frac{1}{2} \right)}^{10}}=\frac{63}{{{2}^{9}}}\]You need to login to perform this action.
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