Question

in 1920 the record for a certain race was 45.7 seconds. In 1930, it was 45.4 seconds. Let R(t)= the record in the race and t = the number of years since 1920.
Find the linear function that fits the data.R(t)=__ (round to nearest hundreth.
What is the predicted record for 2003?__
What is the predicted record for 2006?__
In what year will the predicted record be 42.79 seconds?__

Answer 1

treat your data as consisting of the two ordered pairs
(0, 45.7) and (10, 45.4)

find the slope, and find the equation in the form
f(x) = mx + b form, but you will have
R(t) = .....

the procedure is the same.

Once you have the equation , for the record in 2003, let t = 83

BTW, the question is unrealistic, eventually the record will reach zero, and you will have "time-travel"