Question 365401
while going speed = 45 mph
distance be x
{{{time = Distance / speed}}}
so 
time to go to grand Canyon = x/45
...
time to return = x/60 
..
total time =7 hours
..
x/45+x/60 = 7
60x+45x / 60*45 =7
105x=7*45*60
/105
x=7*45*60/105
=180 miles
...
m.ananth@hotmail.ca