Question 960798
d=distance between cities
{{{d/(40km/hr)+d/(60km/hr)=8hrs}}} Find common denominator
{{{(1.5/1.5)(d/(40km/hr))+d/(60km/hr)=8hrs}}}
{{{(1.5d)/(60km/hr)+d/(60km/hr)=8hrs}}}
{{{2.5d/(60km/hr)=8hrs}}} Multiply each side by (60km/hr).
{{{2.5d=(8hrs)(60km/hr)}}}
{{{2.5d=480km}}} Divide each side by 2.5.
{{{d=192km}}} ANSWER: The cities are 192 kilometers apart.
CHECK:
{{{d/(40km/hr)+d/(60km/hr)=8hrs}}}
{{{(192km)/(40km/hr)+(192km)/(60km/hr)=8hrs}}}
{{{4.8hrs+3.2hrs=8hrs}}}
{{{8hrs=8hrs}}}