we are given relation between speed and distance
distance ( when speed =70mph) is
=328feet
so, [tex]d_1=328[/tex]
distance ( when speed =50mph) is
=183feet
so, [tex]d_2=183[/tex]
now, we can find percentage in decrease
[tex]=\frac{d_1-d_2}{d_1}\times 100[/tex]
now, we can plug values
[tex]=\frac{328-183}{328}\times 100[/tex]
[tex]=44[/tex]%...........Answer
