Answer
$μ=0.9323~rocket~hits$
Work Step by Step
Total number of rockets: $229+211+93+35+7+0+0+1=576$
$μ=ΣxP(x)=0\times\frac{229}{576}+1\times\frac{211}{576}+2\times\frac{93}{576}+3\times\frac{35}{576}+4\times\frac{7}{576}+5\times\frac{0}{576}+6\times\frac{0}{576}+7\times\frac{1}{576}=\frac{537}{576}=0.9323$
