Answer
$1.03$
Work Step by Step
We will need to know that: $pH= -log[H_{3}O^{+}]$ and that the $[H_{3}O^{+}]$in a strong acid solution is equal to the concentration of that strong acid because strong acids completely dissociate in solution. Therefore, we can plug the concentration of strong acid in place of that of $H_{3}O^{+} $in the pH equation to get our answer.
Since $HClO_{4}$ and $HCl$ are strong acids we can add their concentrations together in our equation:
$pH= -log(0.045+0.048)$
$pH=1.03$
