Question 1033486
Two cars started at sunrise and each travelled at a constant speed,
one from city A to city B and the other from city B to city A on the same highway.
they met at noon and without stopping and arrived at city B at 4 p.m and at city A at 9 p.m.
required: Determine the sunrise time for that day 
:
let t = time from sunrise to noon
then
t/9 = Ratio of the time of each from A to the noon position
and
4/t = Ratio of the time of each from the noon position to B
:
these ratios should be equal, therefore:
 {{{t/9}}} = {{{4/t}}}
Cross multiply
t^2 = 4 * 9
t^2 = 36
t = 6 hrs
Sunrise would be 6 hrs from noon which is 6 AM