An aeroplane leaves an airport and files due north at a speed of 1000 km/hr. At the same time, another aeroplane leaves the same airport and files due west at a speed of 1200 km/hr. How far apart will be the two planes after 
hours?
Distance traveled by the plane flying towards north in 11/2 hrs
=1000x1
=1500km
Similarly Distance traveled by the plane flying towards west in 11/2hrs
=1200x1
=1800 km
Let this distance is represented by OA and OB
Distance between these place after 1
hrs AB=
= 
=
=
=
=300
=300x7.8102
= 2343.07 km
So, distance between these places will be 2343 km (Approx) km, after 1 1/2 hrs
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