0.25mol of CO are mixed with 0.90mol of H2 and heated to 950 degrees celcius in a 15L flask at equilibrium 0.190mol of H2O were present, what is the concentration of the other reactants and products at equilibrium and what is Kc

Are you sure this is the equation?

(CO) = 0.25/15 L = about 0.0167M
(H2) = 0.90/15 L = about 0.06 M

........CO + H2 ==> H2O + C
I....0.0167.0.060....0.....0
C.......-x...-x.......x....
E.....0.0167-x.0.060-x..x

(H2O) = 0.190/15 L = about 0.0127 = x
Then 0.0167-x = ?
and 0.060-x = ?

Substitute into Kc expression and solve for Kc.