SCIN130 Final Exam

55 million liters

725000 (extra population in a year if you deduct nr of death from nr. of birth) * 75liters per person = 54,375,000 liters

thank you

Thanks andalitza, so what's the underlying formula you have to use? What's the formula called?

there is no formula really
the problem asks you to figure out the amount of water per day for the newly added population during a year
and since you have the birth rate and death rate, to find the newly added population you have to subtract the nr. people that died from the nr. of new born people.
the rate is given per 1000, so how many 1000 are in 25,000,000?
that is  25,000,000/1000 = 25,000
birth rate is 32 per 1000, so the number of new born people for a year is 25,000*32=800,000
you do the same with the death rate: 3 per 1000,  25,000*3=75,000
now subtract people that died in a year from people that were born that year:
800,000-75,000 = 725,000 newly added people in a year to the original population of 25,000,000
now you can find out the amount of liters of water:
725,000people * 75 liters = 54,375,000 liters