\[P = P_{10}(8) + P_{10}(9) + P_{10}(10);\text{\ \ \ }\]
\[p = 0,5;\text{\ \ \ }\]
\[q = 1 - 0,5 = 0,5;\]
\[= {0,5}^{10} \bullet \left( \frac{10 \bullet 9 \bullet 8!}{8! \bullet 2} + 10 + 1 \right) =\]
\[= \frac{45 + 11}{2^{10}} = \frac{56}{2^{10}} = \frac{7}{2^{7}} = \frac{7}{128}.\]
\[Ответ:\ \ \frac{7}{128}.\]