KOH --> K+ + OH-
pH + pOH = 14
pOH = -log10([OH-]) = -log10(7.4*10-2)
pH = 14 - (-log10(7.4*10-2))
$${\mathtt{pH}} = {\mathtt{14}}{\mathtt{\,\small\textbf+\,}}{log}_{10}\left({\mathtt{7.4}}{\mathtt{\,\times\,}}{{\mathtt{10}}}^{-{\mathtt{2}}}\right) \Rightarrow {\mathtt{pH}} = {\mathtt{12.869\: \!231\: \!719\: \!730\: \!976\: \!2}}$$
or pH ≈ 12.9
KOH --> K+ + OH-
pH + pOH = 14
pOH = -log10([OH-]) = -log10(7.4*10-2)
pH = 14 - (-log10(7.4*10-2))
$${\mathtt{pH}} = {\mathtt{14}}{\mathtt{\,\small\textbf+\,}}{log}_{10}\left({\mathtt{7.4}}{\mathtt{\,\times\,}}{{\mathtt{10}}}^{-{\mathtt{2}}}\right) \Rightarrow {\mathtt{pH}} = {\mathtt{12.869\: \!231\: \!719\: \!730\: \!976\: \!2}}$$
or pH ≈ 12.9