A cistern 6 m long, 4 m wide, contains water to a depth of 1 m 25 cm : find the area of the wet surface.

The wet surface will be: the base 6X4=24 m

^{2 }plus 2 walls of 1.25X4 = 10m^{2}plus two walls of 1.25X6 = 15m^{2}total 24+10+15=49m

^{2}