Atomic nucleus questions

Which of the following isotopes is the most likely $X$X in the reaction $^{236}_{92} U \rightarrow ^{92}_{36} Kr + 3 n + X$start subscript, 92, end subscript, start superscript, 236, end superscript, U, right arrow, start subscript, 36, end subscript, start superscript, 92, end superscript, K, r, plus, 3, n, plus, X, where $n$n denotes a free neutron?