Question 144491
You are given two points, so first find the slope between them.

slope = (y2 - y1)/(x2 - x1)
slope = (66.8 - 63.7)/(1999 - 1993)
slope = 3.1/6 = 0.516

{{{E(t) = 0.516t + 63.7 }}} is an equation for a line that represents the life expectancy of a males, where t is the number of years starting at 1993.

So, using this equation, we see that in 1193, t = 0  (year - 1993)
This yields 63.7

In the year 1999, t = (1999-1993) = 6
E(6) = 0.516(6) + 63.7 = 66.8

Now let's assume the same model is OK through 2007. t = (2007 - 1993) = 14
E(14) = 0.516*14 + 63.7
E(14) = 70.924

Make sense?