What is [K+] when mixing two separate solutions and when given the Ksp.?

Question

The solubility product constant for K2PdCl6 is 6.0 x 10^-6 (K2PdCl6 --><-- 2k+ + PdCl6 2-). What is the K+ concentration of a solution prepared by mixing 50.0 mL of a 0.400 M KCl with 50.0 mL of 0.100 M PdCl6 2-?

I have the entire problem worked out since a teacher gave it to me but am not understanding why they are doing some of the things they are doing. Once you find the moles of K+ from KCl by multiplying molarity times volume, it is confusing me as to what happens afterwards.

Answer 1

Basically , nearly all of the K+ ends up as the K2PdCl6. Approximations are made to get [K+].