SOLUTION: This table shows the world record times in the men's 100 meter dash from 1912 to 2009. In year 1912 the world record was 10.6 1921 - 10.4 1930- 10.3 1936-10.2 1956-10.1 19

Algebra ->  Linear-equations -> SOLUTION: This table shows the world record times in the men's 100 meter dash from 1912 to 2009. In year 1912 the world record was 10.6 1921 - 10.4 1930- 10.3 1936-10.2 1956-10.1 19      Log On


   

Question 1131104: This table shows the world record times in the men's 100 meter dash from 1912 to 2009.
In year 1912 the world record was 10.6
1921 - 10.4
1930- 10.3
1936-10.2
1956-10.1
1960-10.0
1968-9.9
1999-9.8
2008-9.7
2009-9.6
Write an equation for a linear model representing the data. Define your variables.
Using your model, when will your model fall betlow 9.2 seconds? What year?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
given:
1912 -+10.6
1921+-+10.4
1930- 10.3
1936-10.2
1956-10.1
1960-10.0
1968-9.9
1999-9.8
2008-9.7
2009-9.6+

a.
For your data, the regression equation for+y is:
Sum of x+=+19599
Sum of y+=+100.6
Mean Mean+%5Bx%5D+=+1959.9
Mean Mean+%5By%5D=+10.06
Sum of squares %28SSx%29+=+11606.9
Sum of products+%28SP%29+=+-101.14
Regression Equation =>+y+=+bx+%2B+a
b+=+SP%2FSSx+=+-101.14%2F11606.9+=+-0.00871
a+=+Mean+%5By%5D+-+bMean+%5Bx+%5D=+10.06+-+%28-0.01%2A1959.9%29+=+27.13814
y+=++-0.00871%2Ax+%2B+27.13814


Using your model, when will your model fall bellow 9.2 seconds? What year?


y+=-0.00871%2A9.2+%2B+27.13814
y+=+-0.080132%2B+25.70866
y+=+25.628528

in second half of the year 2034