Question

An aeroplane takes 4 hr to travel a distance of 1200 km. Another aeroplane travels at a speed which is 100 km per hour lesser than the first. How long will both take to cover 1500 km distance.​

Answer 1

Step-by-step explanation:

time taken for the airplane to travel 1200km=4hrs.

time taken by the plane to travel one kilometre is equal to 4/1200 hrd

for 500 km it takes 4/1200×500

ie.5/3 hrs or100 mins

speed of the plane 1200/4

ie. 300km/hr. ans.

2nd plane

speed=300-100km/hr

ie. 200km/hr

therefore time taken by the plane to travel 500km=500/200hrs

ie. 2.5hrs. ans.

Answer 2

1st Aeroplane:

Speed = Distance traveled

               Time covered

= 1200km

  4hours

= 300km/hr

2nd Aeroplane

Speed = 300km/hr - 100km/hr

= 200km/hr

To cover 1,500km for the 1st Aeroplane

Speed = Distance traveled

               Time covered

= 1,500km

 300km/hr

= 5 hours

To cover 1,500km for the 2nd Aeroplane

Speed = Distance traveled

               Time covered

= 1,500km

 200km/hr

= 15 hrs

   2

= 7 $\frac{1}{2}$ hours