Question 1164102
.
<pre>

Let Jamill's distance be d and Jamill's time be t.


Let Jacob's distance be x  and Jacob's time be y.



Then  d = x + x/4 = {{{(5/4)*x}}},  and  y = {{{(11/10)*t}}}.


It implies  x = {{{(4/5)*d}}}.


Then Jamill's speed is  {{{d/t}}},  while the Jacob' speed is  {{{x/y}}} = {{{((4/5)*d)/((11/10)*t)}}} = {{{((4*10)*d)/((5*11)*t)}}} = {{{(40/55)*(d/t)}}}.


Therefore, the ratio of the Jamill' speed to that of Jacob is  {{{40/55)}}} = {{{8/11}}}.    <U>ANSWER</U>
</pre>

Solved.