Estimate from depth-area curve, the average depth of precipitation that may be expected over an area of 2400 Sq. km due to the storm of 27th September 1978 which lasted for 24 hours. Assume the storm centre to be located at the centre of the area. The isohyetal map for the storm gave the areas enclosed between different isohyetes as follows: Isohyet (mm) Enclosed area (km) 18 21 20 19 54 134 203 254 3 5 0 5 17 295 5 328 16 15 14 13 12 353 371 388 391 5 0 500