posted by sonia .
In 1990, the life expectancy of males in a certain country was 66.3 years. In 1997, it was 70.0 years. Let E represent the life expectancy in years t and let t represent the number of years since 1990. E(t)= ___t +____ round to the nearest tenth. Use the fuction to predict life expectancy of males in 2009. E (19) =______ round to the nearest tenth. I'm sorry I tried and I can not get this problem
I didn't get it either, until I erad the question for the equation three times. It seems they're assuming that the life expectancy function plotted agaist the years since 1990 is a straight line, and I'm not at all sure you should assume that.
Anyway, if we do assume it, then we end up with a straighforward question.
You could think of it as:
solve y = mx + c given two points:
(0, 66.3) and (7, 70.0)
Does that help enough?