# math 117/algebra

The US population 1990 was approximately 250 million, and the average growth rate for the past 30 years gives a doubling time of 66 years. The above formula for the US then becomes P(in millions) = 250 x 1(y - 1990)/66
(1) What will the population of the US be in 2025 if this growth rate continues?
(2) If there are 6 x ¡¼10¡½^9 people on the Earth and there si enough freshwater to provide each person with 8.79 x ¡¼10¡½^5 L, how many liters of water does the US use each year?

The formula should be

P(in millions) = 250 x 2(y - 1990)/66

or P=250 x 235/66

Do that on your calculator with the yx key

A US citizen uses more fresh water than the world average, just as we use more petroleum and many other resources. Therefore your question cannot be answered with the information provided.
Is your ¡¼10¡½ supposed to be a 10 ?

no it is actually 6 x 10 to the 9th and 8.79 x 10 to the 5th l

If the average US resident used the average world amount, the US consumption would be (assuming 300 million people in the USA)
3*10^8 people x 8.79*10^5 liters/person

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