a binomial probability experiment is conducted with the given parameters compute the probability of x successes in the n independent trials of the experiment
n=20 p=0.7 x ≥ 12

2. $P(X \geqslant 12) = \sum\limits_{k = 12}^{20} {{{20} \choose k} \left( {0.7} \right)^k \left( {0.3} \right)^{20 - k} }$