Posted by **Liz** on Thursday, March 11, 2010 at 1:38am.

In 1920, the record for a certain race was 46.6 sec. In 1980, it was 45.4 sec. Let R(t)= the record in the race and t = the number of years snce 1920.

a) Find a linear function that fits the data R(t) =

b) Use the function in (a) to predict the record in 2003 and in 2006.

2003 =

2006 =

c) Find the year when the record will be 46.68 sec.

- Math -
**FredR**, Thursday, March 11, 2010 at 7:03pm
From 1920 to 1980 is 60 years. The record was shortened by 1.2 seconds. The slope of the line is the rise over the run, or:

-1.2/60

for t=0, R(t) = 46.6 so the y intercept is 46.6.

The format of a line is y = mx + b where m is the slope and b is the y intercept. So,

a) so the line would have the formula:

R(t) = -(1.2/60)t+46.6

b) substitute t=2003-1920 into part a and solve for R(t)

substitute t=2006-1920 into part a and solve for R(t)

c) substitute R(t) = 46.68 into part a and solve for t

## Answer this Question

## Related Questions

Math - In 1920, the record for a certain race was 46.6 sec. In 1980, it was 45.4...

algebra - ok i dont get this one in 1920 the record for a certain race was 45.9 ...

math - In 1920, the record for a certain race was 45.5 sec. In 1970, It was 44.5...

Algebra 1 - in 1920, the record for a certain race was 45.8 sec. In 1980, it was...

Math - how do I solve this problem. In 1920 the record for a certain race was ...

math - in 1920 the record for a certain race was 46.4 sec. In 1960 it was 45.6 ...

math (am i correct) - in 1920 the record for a certain race was 46.9 sec. In ...

math - in 1920 the record for a certain race was 46.9 sec. In 1990 it was 45.5 ...

algebra - In 1920 the record for a certain race was 45.4 sec. in 1950, it was 41...

Math 116 - In 1920, the record for a certain race was 45.7 sec. In 1950, it was ...