A bed of sand 12 m thick is underlain by a compressible stratum of normally loaded clay, 6 m thick. The water table is at a depth of 5 m below the ground level. The unit weight of sand above and below water table are 17.5 kN/m3 and 20.5 kN/m3 respectively. The clay has a natural water content of 40% and LL of 45% and Gs=2.75. Estimate the probable final settlement if the average increment in pressure due to foundation is 100 kN/m2