An equilibrium mixture of the reaction \[2N{{O}_{(g)}}+{{O}_{2(g)}}\] \[2N{{O}_{2}}_{(g)}\] contains \[0.12moles\]of\[N{{O}_{2}}\], \[0.08moles\]of \[NO\]and \[0.64\text{ }moles\]of \[{{O}_{2}}\] in a 4 litre flask at constant temperature. The value of \[{{K}_{c}}\] this temperature is: