Applied Calculus
posted by Jacob .
The world population at the beginning of 1990 was 5.3 billion. Assume that the population continues to grow at the rate of approximately 2%/year and find the function Q(t) that expresses the world population (in billions) as a function of time t (in years), with t = 0 corresponding to the beginning of 1990. (Round your answers to two decimal places.)
(a). If the world population continues to grow at approximately 2%/year, find the length of time t0 required for the population to double in size.
t0=____yr
(b). Using the time t0 found in part (a), what would be the world population if the growth rate were reduced to 1.2%/yr?
____ billion people
I don't understand how to set this problem up correctly.

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