Answer
See below
Work Step by Step
The probability of tossing a coin 30 times and getting 27 heads can be found by applying: $P(X=27)=_nC_k p^k (1-p)^{n-k}\\=_{30} C_{27} 0.5^{27}(1-0.5)^{30-27}\\=\frac{30!}{(30-27)!.27!}\times0.5 ^{30}\\=3.78\times10^{-6}$