Question

Can anyone please do question number 18

Answer 1

Let Ajay takes X hours to cover distance of 40 km.

Therefore Raju takes ( 4 + x)hour to cover a distance of 40 km.

Raju 's speed = (Distance /Time)

(40/4 + x)

when Raju doubles his speed then

( 40/4+x)*2 = (3/2 + x) hours.

On equating ;

80/8+2x =3/2 + x

80/8+3x = 3/2

3x = 3/2*80/8

3x = 15

x=15/3

x=5

Then speed of Ajay = ( 40/5) km/hour= 8 km/hour.

Then speed of Raju = ( 40/9 ) km/hour = 40/9 km/hour

Answer 2

refer the attachment!!! hope it helps !!!