The pH of a solution obtained by mixing \( 50 \, \text{mL} \) of \( 1 \, \text{M} \) HCl and \( 30 \, \text{mL} \) of \( 1 \, \text{M} \) NaOH is \( x \times 10^{-4} \). The value of \( x \) is ________ . (Nearest integer) [\( \log 2.5 = 0.3979 \)]
