Question

A bus traveled a certain average speed for a distance and then travels a distance 90 km at an average speed 10 km/h more than first speed if it takes 3 hours to complete whole journey find first speed

Answer 1

Solution :

Distance travelled by the bus = 75 km

Let the average speed =xkm/hr

Distance travelled =90km

the average speed during this distance =(x+10)km/hr

DS=t

Total time taken =3hr

752+90x+10=3

=75(x+10)+90xx(x=10)=3

165x+750=3x2+30

=> 3x2±135x−750=0

=> x2−45x−250=0

(x−50)(x+5)=0

x=−5 is not admissible.

Hence =50km/hr