[jd87]

I don't even know how to approach this question...I'm not sure where/how to use the value of the platinum electrode potential given..

Given the following half-reactions:
 Ce4+ + e− → Ce3+      E° = 1.72 V 
 Fe3+ + e− → Fe2+      E° = 0.771 V 

What volume of 0.88 M Ce4+ solution must be mixed with 34 mL of 0.82 M Fe2+ solution to produce a solution which produces a platinum electrode potential (relative to SHE) of 1.2455 V.