According to the US Department of Agriculture in 2005 the US

According to the U.S. Department of Agriculture, in 2005, the U.S. exported 14.0 million liters of fruit juice and wine. In 2011, that number was 17.3 million liters.

Assuming the increase in exports is linear, write an equation that gives the number of million liters exported in year x , with x=5 corresponding to 2005.

What is the value of exports in the 2014 assuming the same trend continues?

Solution

at x=5,
export, e = 14

at x=11,
export, e = 17.3

the linear equation will be:
(e-14)/(x-5) = (17.3-14)/(11-5)
(e-14)/(x-5) = 3.3/6
6e - 84 = 3.3*x - 16.5
6e = 3.3*x + 67.5
e = 0.55*x + 11.25
So linear equation is
e(x) = 0.55*x + 11.25

in 2014:
x=14
e = 0.55*14 + 11.25 =18.95 million litres
Answer: 18.95 million litres