Question 1203958
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hello! i need help! i am trying to solve a word problem but i can't figure it out! the word problem is: 
"the number of acres of farmland in the US has decreased at a relatively constant rate of 3.27 million acres 
per year from 1987 to 1997. in 1997, there were 931.8 million acres of farmland." 
i have to write an equation that gives the number of acres of farmland as a function 
of the number of years since 1987. then i have to predict when the number of acres will fall below 915 million acres.
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<pre>
Based on the given data in the problem, you write the function

    A(t) = 931.8 - 3.27*t 

for acres in use (in millions acres), where t is the time, in years, after 1997.


By making it, you {{{highlight(highlight(assume))}}}  that  <U>the average rate remains the same after 1997</U>.  

So, your  "prediction" equation is 


    931.8 - 3.27*t = 915.


From this equation, you find t, the time in years after 1997

    t = {{{(931.8-915)/3.27}}}.


Then you use your calculator and find  t = 5.13  years.


It means that this area of 915 millions acres in use will be reached in the year 1997 + 5 = 2002.


<U>ANSWER</U>.  The prediction is the year 2002.
</pre>

Solved.