Question

a train travels at a certain average speed for a distance of 63 km and then travels for a distance of 72 km at an average speed of 6km/hr more than its original speed. if it takes 3 hours to complete the total journey, find the original average speed

Answer 1

HEY FRIEND HERE YOUR ANSWER

Given that distance = 63 km.

Let original speed of train = x km/hr.

time = distance / time = 63/x hrs.

And it travels a distance of 72 kkm at a average speed of 6 km/hr more than the original speed.

distance = 72 km ; speed = (x + 6) km/hr .

time = 72/(x+6) hrs. If it takes 3 hours to complete the whole journey

63/x + 72/(x + 6) = 3 hrs

⇒ 63(x + 6) + 72x = 3x(x + 6)

⇒ 21(x + 6) + 24x = x(x+6)

⇒ 45x + 21×6 = x + 6x

⇒ x - 39x - 126 = 0

⇒ x - 39x - 126 = 0

⇒ (x - 42)(x + 3) = 0

∴ x = 42 km/hr

∴ the original average speed = 42 km/hr

I HOPE IT'S HELP YOU

MARK BRAINLIEST MY ANSWER DEAR FRIEND

Answer 2

Hey frnd..........^_^.