2. The population of a town in three consecutive years are 5000, 7000 and 8400 respectively. The population of the town in the fourth consecutive year according to geometrical increase method is 10920.
3. A water supply scheme has to be designed for a city having a population of 100, 000. If annual average daily consumption of water is 250 lpcd, then maximum daily draft will be 45 Mld. (1.8* average)
4. If annual average daily draft of water is 270 lpcd and population of the city is 2,00,000, then peak demand will be 145.8 Mld.
5. A water supply scheme has to be designed for a city having a population of 1,00,000. If annual average daily draft is 250 lpcd, then coincidental draft will be(Fire draft can be calculated using formula Q= 4637.P^(1/2) [(1 - 0.001.P^(1/2) ], where P is in thousands and Q is in litres/min. is 106 Mld.
6. Assuming the arithmetical increase method, population of the town in the year 1991 with the help of following census records of the population i.e. population in the years 1951, 1961 and 1971 are 255, 495 and 735 thousands respectively, will be 1015.
7. If 50,000 litres daily of industrial waste water containing 2000 mg/lit of suspended solid, then population equivalent of this sewage if per capita contribution of suspended solids is 75 gm, will be 167.
8. The chlorine demand of a water sample was found to be 0.5 mg/lt. The amount of bleaching powder containing 30% available chloride to be added to treat one litre of such a water sample is 1.67
9. A water treatment work treats 6000 m^3 of water per day. If it consumes 20 kg chlorine per day then chlorine dosage would be 3.33 mg/lit.
10. A city supply of 16000 cubic metres of water per day treated with chlorine with dosage of 0.6 ppm. For this purpose, requirement of 30% bleaching powder per day would be 32 kg.
Reference: GK Publishers.