First of all apparently the height equals 10 inches not feet.
So the horizontal distance = (24-6)/12 = 1.5 feet and the vertical distance = 5/6 feet
With that said let us solve it using the formula that work equals change in energy.
W = K.E.2 + U2 - (K.E.1 + U1)
As you said K.E.1 + U 1 equals...