$$Common\:interval\:\left(h\right)=15$$

$$Waterplane\:area\:\left(A_{w}\right)=2\times\frac{h}{3}\sum A$$

$$=2\times\frac{15}{3}\times190$$

$$=1900m^2$$

$$Longitudinal\:centre\:of\:flotation\:LCF=h\times\frac{\sum M_{A}+\sum M_{F}}{\sum A}$$

$$=15\times\frac{174-122}{190}$$

$$LCF=4.105m$$

$$A_{w}=\frac{100\:\times\:TPC}{\rho}$$

$$TPC=\frac{1.025\times1900}{100}$$

$$TPC=19.475m^2$$

$$Second\:moment\:about\:midships\:\left(I_{m}\right)=2\times\frac{h^3}{3}\sum I$$

$$=2\times\frac{15^3}{3}\times646$$

$$I_{m}=1453500m^4$$

$$Second\:moment\:of\:area\:about\:centroid\:\left(I_{F}\right)=I_{m}-A_{w}\times TPC^2$$

$$1453500-\left(1900\times41.05^2\right)$$

$$I_{F}=1421483m^4$$