Question

ajay covers a distance of 240 km in 17/4 hours.some part of the journey was covered at a speed of 45 kmph and the rest by 60 kmph . find the distance he covered in 60 mph

Answer 1

Answer:

Speed= D/T

Let distance covered with speed 45kmph be x and 60kmph be y

D= S×T

T=D/S

240= 45x + 60y— eq 1

17/4= x/45 + y/60—eq 2

for sake of convenience, multiply eq 2 by 180 then by 20.

765= 4x + 3y

15300= 80x + 60y

subtract eq 1 from 2

15300= 80x + 60y

(-)240= 45x + 60y

15060= 35x

x= 15060/35

x= 430

substitute value of x in eq to find y.