Question 1131104
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 [x] = 1959.9}}}
Mean {{{Mean [y]= 10.06}}}
Sum of squares {{{(SSx) = 11606.9}}}
Sum of products{{{ (SP) = -101.14}}}

Regression Equation =>{{{ y = bx + a}}}

{{{b = SP/SSx = -101.14/11606.9 = -0.00871}}}

{{{a = Mean [y] - bMean [x ]= 10.06 - (-0.01*1959.9) = 27.13814}}}

{{{y =  -0.00871*x + 27.13814}}}



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



{{{y =-0.00871*9.2 + 27.13814}}}

{{{y = -0.080132+ 25.70866}}}

{{{y = 25.628528}}}


in second half of the year {{{2034}}}