Please explain to me how this question was answered. The question and its corresponding answer are attached but i need an explanation for how the answer was obtained because i dont understant it.

\fdirty : x : # of broken spike un to Ems of rail road Sx : Some spack of * Sx - ho, 1, l, - -. 7 Kmy given that 12 broken spikes, on both of railroad spiked are independent of each other 27 40 * 12 spikes on on my on 6 0D No knis of railroad . brokem spiken on an average on 40 kno of rail road 2 X N Poi ( 2 = 4, 5 ) S. + pix= x]- e's ( 45) 21 To find : PL at least one broken spike ] = P ( x >, 1 ] = ? 8017 : P [ x > 1 ] - 1 - P(x=0] 6 1 = 1 - 0. 44 933 = 0 . 5507 Ans PL finding out last one broken spike in the next dio kno] = 0. 5507