Question 67 – In order to predict the wastewater production, the population number has to be understood. The population data is : 72000 (for year 1961 or P-1961), 85000 (for year 1971 or P-1971), 110500 (for year 1981 or P-1981). (a) Find the average population increase, or [ (P-1981 - P-1971) + (P-1971 - P-1961) ] / 2. (b) Find the average percentage population increase, or [ (P-1981 - P-1971) / P-1971 + (P-1971 - P-1961) / P-1961 ] / (2) X 100. (c) Find the incremental increase or P-1981 - 2 (P-1971) + P-1961. (d) Let Po = P-1981. After 2 decades or n = 2, the population is P-2001. By using arithmetical increase method, find P-2001 = Po + n (Answer for a). (e) By using incremental increase method, find P-2001 = (Answer of d) + n (n + 1) (Answer of c) / 2. (f) By using geometrical increase method, find P-2001 = Po [ 1 + (Answer of b) / 100 ] ^ n where ^ is power sign, or 1 ^ 2 = 1 x 1 = 1. (g) If the actual P-2001 = 184000, which method of estimation is more accurate, based on your answer in (d), (e) and (f)?
Answer Posted / kang chuen tat (malaysia - pen
Answer 67 – (a) Average population increase = [ (110500 - 85000) + (85000 - 72000) / 2 = 19250. (b) Average percentage population increase = [ (85000 - 72000) / 72000 + (110500 - 85000) / 85000 ] x 100 / 2 = 24.025. (c) Incremental increase = 110500 - 2 (85000) + 72000 = 12500. (d) P-2001 = 2(19250) + 110500 = 149000. (e) P-2001 = 149000 + 2 (3) (12500) / 2 = 186500. (f) P-2001 = 110500 (1 + 0.24025) ^ 2 = 169973. (g) Errors of answers : (d) 184000 - 149000 = 35000, (e) 184000 - 186500 = -2500, (f) 184000 - 169973 = 14027. Answer (e) or incremental increase is more accurate to such data, or the most accurate prediction among the three available formulae. The answer is given by Kang Chuen Tat; PO Box 6263, Dandenong, Victoria VIC 3175, Australia; SMS +61405421706; chuentat@hotmail.com; http://kangchuentat.wordpress.com.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
Is there any way to slow coke formation in ethylene furnaces?
Name the three classes of organic solvents?
At what temperature does water have maximum density?
How can we derive power factor equation p=vi cos phi?
Is it ever advantageous to use shells in series even though it may not be necessary?
What are the specialized crushing methods?
What is an effective means of removing silicon from aluminum?
How can the particle size distribution be determined in a given bulk solid?
Name some common causes of control valve noise?
What is a 'saltation velocity' and how is it used in designing pneumatic conveying systems?
Explain what is the method involved in analyzing powders for composition?
Re: Sugar Cane Bagasse What are the 1. Specific Heat of Bagasse at 50% moisture, 40% moisture and 25% moisture? 2. What is bu;lk density of bagasse at 50% moisture, 40% moisture and 25% moisture? 3. What is specific gravity of bagasse at 50% moisture, 40% moisture and 25% moisture? 4. What is the specific heat of flue gases generated from boiler fuelled by bagasse? 5. What is the specific gravity of flue gases generated from boiler fuelled by bagasse?
For a given bulk solid how can the particle size distribution be determined?
How do you design a vapor-liquid separator or a flash drum?
How does hollow shaft impeller works? Does it based on principle of pitot tube?