two planes 1 and 2 hit a plane in succession . the probability of 1 and2 scoring hit correctly is 0.3 and 0.2 respectively. The second plane will bomb only if 1misses it. probability the target is hited by 2nd one
ans-0.32
-
UP 0 DOWN 0 0 1
1 Answers
62The probability fo 2 hitting is
\\.7\times.2+.7\times.8\times.7\times.2+.7\times(.8\times.7)^2\times.2+.7\times(.8\times.7)^3\times.2++.7\times(.8\times.7)^4\times.2+... \\=\frac{.7\times.2}{1-.8\times.7}=\frac{.14}{.44}