[Dharma Bum]

Mix together the following two solutions:

Solution 1 (consisting of the following three components):
    59.7 mL of distilled water
    26.1 mL of pH = 5.1 buffer solution
    22.47 mL of 0.11 M KIO3 solution

Solution 2:
    56.03 mL of 0.15 M KI(aq)

calculate the initial concentration of IO3-(aq), [IO3-]ini, after the two solutions described below are mixed.

I'm not too sure how I'd even get started on this one, do I just consider the IO3 from the KIO3 solution and dilute it appropiately, or does the PH from the buffer solution play a role? Thanks.

[AWK]

You should check at which pH the reaction:
5I^- + IO₃^- + 6H⁺ = 3I₂ +3H₂
can start.
If you can neglect this reaction - calculations are quite simple